run_transformers_training.py

#!/usr/bin/env python3
# -*- coding: utf-8 -*-

# Basic Python imports
import os
import sys
import json
import argparse
import logging
from datetime import datetime
import time
import warnings
import traceback
from importlib.util import find_spec
import multiprocessing
import torch
import random
import numpy as np
from tqdm import tqdm

# Check hardware capabilities first
CUDA_AVAILABLE = "CUDA_VISIBLE_DEVICES" in os.environ or os.environ.get("NVIDIA_VISIBLE_DEVICES") != ""
NUM_GPUS = torch.cuda.device_count() if CUDA_AVAILABLE else 0
DEVICE_TYPE = "cuda" if CUDA_AVAILABLE else "cpu"

# Set the multiprocessing start method to 'spawn' for CUDA compatibility
if CUDA_AVAILABLE:
    try:
        multiprocessing.set_start_method('spawn', force=True)
        print("Set multiprocessing start method to 'spawn' for CUDA compatibility")
    except RuntimeError:
        # Method already set, which is fine
        print("Multiprocessing start method already set")

# Import order is important: unsloth should be imported before transformers
# Check for libraries without importing them
unsloth_available = find_spec("unsloth") is not None
if unsloth_available:
    import unsloth

# Import torch first, then transformers if available
import torch
transformers_available = find_spec("transformers") is not None
if transformers_available:
    import transformers
    from transformers import AutoTokenizer, TrainingArguments, Trainer, TrainerCallback, set_seed
    from torch.utils.data import DataLoader

peft_available = find_spec("peft") is not None
if peft_available:
    import peft

# Only import HF datasets if available
datasets_available = find_spec("datasets") is not None
if datasets_available:
    from datasets import load_dataset

# Set up the logger
logger = logging.getLogger(__name__)
log_handler = logging.StreamHandler()
log_format = logging.Formatter('%(asctime)s - %(levelname)s - %(message)s')
log_handler.setFormatter(log_format)
logger.addHandler(log_handler)
logger.setLevel(logging.INFO)

# Define a clean logging function for HF Space compatibility
def log_info(message):
    """Log information in a format compatible with Hugging Face Spaces"""
    # Just use the logger, but ensure consistent formatting
    logger.info(message)
    # Also ensure output is flushed immediately for streaming
    sys.stdout.flush()

# Check for BitsAndBytes
try:
    from transformers import BitsAndBytesConfig
    bitsandbytes_available = True
except ImportError:
    bitsandbytes_available = False
    logger.warning("BitsAndBytes not available. 4-bit quantization will not be used.")

# Check for PEFT
try:
    from peft import LoraConfig, get_peft_model, prepare_model_for_kbit_training
    peft_available = True
except ImportError:
    peft_available = False
    logger.warning("PEFT not available. Parameter-efficient fine-tuning will not be used.")

def load_env_variables():
    """Load environment variables from system, .env file, or Hugging Face Space variables."""
    # Check if we're running in a Hugging Face Space
    if os.environ.get("SPACE_ID"):
        logging.info("Running in Hugging Face Space")
        
        # Log the presence of variables (without revealing values)
        logging.info(f"HF_TOKEN available: {bool(os.environ.get('HF_TOKEN'))}")
        logging.info(f"HF_USERNAME available: {bool(os.environ.get('HF_USERNAME'))}")
        
        # If username is not set, try to extract from SPACE_ID
        if not os.environ.get("HF_USERNAME") and "/" in os.environ.get("SPACE_ID", ""):
            username = os.environ.get("SPACE_ID").split("/")[0]
            os.environ["HF_USERNAME"] = username
            logging.info(f"Set HF_USERNAME from SPACE_ID: {username}")
    else:
        # Try to load from .env file if not in a Space
        try:
            from dotenv import load_dotenv
            # First check the current directory
            env_path = os.path.join(os.path.dirname(os.path.abspath(__file__)), ".env")
            
            if os.path.exists(env_path):
                load_dotenv(env_path)
                logging.info(f"Loaded environment variables from {env_path}")
                logging.info(f"HF_TOKEN loaded from .env file: {bool(os.environ.get('HF_TOKEN'))}")
                logging.info(f"HF_USERNAME loaded from .env file: {bool(os.environ.get('HF_USERNAME'))}")
                logging.info(f"HF_SPACE_NAME loaded from .env file: {bool(os.environ.get('HF_SPACE_NAME'))}")
            else:
                # Try the shared directory as fallback
                shared_env_path = os.path.join(os.path.dirname(os.path.dirname(os.path.abspath(__file__))), "shared", ".env")
                if os.path.exists(shared_env_path):
                    load_dotenv(shared_env_path)
                    logging.info(f"Loaded environment variables from {shared_env_path}")
                    logging.info(f"HF_TOKEN loaded from shared .env file: {bool(os.environ.get('HF_TOKEN'))}")
                    logging.info(f"HF_USERNAME loaded from shared .env file: {bool(os.environ.get('HF_USERNAME'))}")
                    logging.info(f"HF_SPACE_NAME loaded from shared .env file: {bool(os.environ.get('HF_SPACE_NAME'))}")
                else:
                    logging.warning(f"No .env file found in current or shared directory")
        except ImportError:
            logging.warning("python-dotenv not installed, not loading from .env file")
    
    if not os.environ.get("HF_TOKEN"):
        logger.warning("HF_TOKEN is not set. Pushing to Hugging Face Hub will not work.")
        
    if not os.environ.get("HF_USERNAME"):
        logger.warning("HF_USERNAME is not set. Using default username.")
    
    if not os.environ.get("HF_SPACE_NAME"):
        logger.warning("HF_SPACE_NAME is not set. Using default space name.")
        
    # Set HF_TOKEN for huggingface_hub
    if os.environ.get("HF_TOKEN"):
        os.environ["HUGGING_FACE_HUB_TOKEN"] = os.environ.get("HF_TOKEN")

def load_configs(base_path):
    """Load configuration from transformers_config.json file."""
    # Using a single consolidated config file
    config_file = base_path
    
    try:
        with open(config_file, "r") as f:
            config = json.load(f)
            logger.info(f"Loaded configuration from {config_file}")
            return config
    except Exception as e:
        logger.error(f"Error loading {config_file}: {e}")
        raise

def parse_args():
    """
    Parse command line arguments for the training script.
    
    Returns:
        argparse.Namespace: The parsed command line arguments
    """
    parser = argparse.ArgumentParser(description="Run training for language models")
    parser.add_argument(
        "--config_file", 
        type=str, 
        default=None,
        help="Path to the configuration file (default: transformers_config.json in script directory)"
    )
    parser.add_argument(
        "--seed", 
        type=int, 
        default=None,
        help="Random seed for reproducibility (default: based on current time)"
    )
    parser.add_argument(
        "--log_level", 
        type=str, 
        choices=["debug", "info", "warning", "error", "critical"],
        default="info",
        help="Logging level (default: info)"
    )
    return parser.parse_args()

def load_model_and_tokenizer(config):
    """
    Load the model and tokenizer according to the configuration.
    
    Args:
        config (dict): Complete configuration dictionary
    
    Returns:
        tuple: (model, tokenizer) - The loaded model and tokenizer
    """
    # Extract model configuration
    model_config = get_config_value(config, "model", {})
    model_name = get_config_value(model_config, "name", "unsloth/phi-4-unsloth-bnb-4bit")
    use_fast_tokenizer = get_config_value(model_config, "use_fast_tokenizer", True)
    trust_remote_code = get_config_value(model_config, "trust_remote_code", True)
    model_revision = get_config_value(config, "model_revision", "main")
    
    # Unsloth configuration
    unsloth_config = get_config_value(config, "unsloth", {})
    unsloth_enabled = get_config_value(unsloth_config, "enabled", True)
    
    # Tokenizer configuration
    tokenizer_config = get_config_value(config, "tokenizer", {})
    max_seq_length = min(
        get_config_value(tokenizer_config, "max_seq_length", 2048),
        4096  # Maximum supported by most models
    )
    add_eos_token = get_config_value(tokenizer_config, "add_eos_token", True)
    chat_template = get_config_value(tokenizer_config, "chat_template", None)
    padding_side = get_config_value(tokenizer_config, "padding_side", "right")
    
    # Check for flash attention
    use_flash_attention = get_config_value(config, "use_flash_attention", False)
    flash_attention_available = False
    try:
        import flash_attn
        flash_attention_available = True
        log_info(f"Flash Attention detected (version: {flash_attn.__version__})")
    except ImportError:
        if use_flash_attention:
            log_info("Flash Attention requested but not available")
    
    log_info(f"Loading model: {model_name} (revision: {model_revision})")
    log_info(f"Max sequence length: {max_seq_length}")
    
    try:
        if unsloth_enabled and unsloth_available:
            log_info("Using Unsloth for 4-bit quantized model and LoRA")
            # Load using Unsloth
            from unsloth import FastLanguageModel
            model, tokenizer = FastLanguageModel.from_pretrained(
                model_name=model_name,
                max_seq_length=max_seq_length,
                dtype=get_config_value(config, "torch_dtype", "bfloat16"),
                revision=model_revision,
                trust_remote_code=trust_remote_code,
                use_flash_attention_2=use_flash_attention and flash_attention_available
            )
            
            # Configure tokenizer settings
            tokenizer.padding_side = padding_side
            if add_eos_token and tokenizer.eos_token is None:
                log_info("Setting EOS token")
                tokenizer.add_special_tokens({"eos_token": "</s>"})
            
            # Set chat template if specified
            if chat_template:
                log_info(f"Setting chat template: {chat_template}")
                if hasattr(tokenizer, "chat_template"):
                    tokenizer.chat_template = chat_template
                else:
                    log_info("Tokenizer does not support chat templates, using default formatting")
            
            # Apply LoRA
            lora_r = get_config_value(unsloth_config, "r", 16)
            lora_alpha = get_config_value(unsloth_config, "alpha", 32)
            lora_dropout = get_config_value(unsloth_config, "dropout", 0)
            target_modules = get_config_value(unsloth_config, "target_modules", 
                ["q_proj", "k_proj", "v_proj", "o_proj", "gate_proj", "up_proj", "down_proj"])
            
            log_info(f"Applying LoRA with r={lora_r}, alpha={lora_alpha}, dropout={lora_dropout}")
            model = FastLanguageModel.get_peft_model(
                model,
                r=lora_r,
                target_modules=target_modules,
                lora_alpha=lora_alpha,
                lora_dropout=lora_dropout,
                bias="none",
                use_gradient_checkpointing=get_config_value(config, "training.gradient_checkpointing", True),
                random_state=0,
                max_seq_length=max_seq_length,
                modules_to_save=None
            )
            
            if use_flash_attention and flash_attention_available:
                log_info("🚀 Using Flash Attention for faster training")
            elif use_flash_attention and not flash_attention_available:
                log_info("⚠️ Flash Attention requested but not available - using standard attention")
                
        else:
            # Standard HuggingFace loading
            log_info("Using standard HuggingFace model loading (Unsloth not available or disabled)")
            from transformers import AutoModelForCausalLM, AutoTokenizer
            
            # Check if flash attention should be enabled in config
            use_attn_implementation = None
            if use_flash_attention and flash_attention_available:
                use_attn_implementation = "flash_attention_2"
                log_info("🚀 Using Flash Attention for faster training")
            
            # Load tokenizer first
            tokenizer = AutoTokenizer.from_pretrained(
                model_name,
                trust_remote_code=trust_remote_code,
                use_fast=use_fast_tokenizer,
                revision=model_revision,
                padding_side=padding_side
            )
            
            # Configure tokenizer settings
            if add_eos_token and tokenizer.eos_token is None:
                log_info("Setting EOS token")
                tokenizer.add_special_tokens({"eos_token": "</s>"})
            
            # Set chat template if specified
            if chat_template:
                log_info(f"Setting chat template: {chat_template}")
                if hasattr(tokenizer, "chat_template"):
                    tokenizer.chat_template = chat_template
                else:
                    log_info("Tokenizer does not support chat templates, using default formatting")
            
            # Now load model with updated tokenizer
            model = AutoModelForCausalLM.from_pretrained(
                model_name,
                trust_remote_code=trust_remote_code,
                revision=model_revision,
                torch_dtype=torch.bfloat16 if get_config_value(config, "torch_dtype", "bfloat16") == "bfloat16" else torch.float16,
                device_map="auto" if CUDA_AVAILABLE else None,
                attn_implementation=use_attn_implementation
            )
            
            # Apply PEFT/LoRA if enabled but using standard loading
            if peft_available and get_config_value(unsloth_config, "enabled", True):
                log_info("Applying standard PEFT/LoRA configuration")
                from peft import LoraConfig, get_peft_model
                
                lora_r = get_config_value(unsloth_config, "r", 16)
                lora_alpha = get_config_value(unsloth_config, "alpha", 32)
                lora_dropout = get_config_value(unsloth_config, "dropout", 0)
                target_modules = get_config_value(unsloth_config, "target_modules", 
                    ["q_proj", "k_proj", "v_proj", "o_proj", "gate_proj", "up_proj", "down_proj"])
                
                log_info(f"Applying LoRA with r={lora_r}, alpha={lora_alpha}, dropout={lora_dropout}")
                lora_config = LoraConfig(
                    r=lora_r,
                    lora_alpha=lora_alpha,
                    target_modules=target_modules,
                    lora_dropout=lora_dropout,
                    bias="none",
                    task_type="CAUSAL_LM"
                )
                model = get_peft_model(model, lora_config)
        
        # Print model summary
        log_info(f"Model loaded successfully: {model.__class__.__name__}")
        if hasattr(model, "print_trainable_parameters"):
            model.print_trainable_parameters()
        else:
            total_params = sum(p.numel() for p in model.parameters())
            trainable_params = sum(p.numel() for p in model.parameters() if p.requires_grad)
            log_info(f"Model has {total_params:,} parameters, {trainable_params:,} trainable ({trainable_params/total_params:.2%})")
        
        return model, tokenizer
        
    except Exception as e:
        log_info(f"Error loading model: {str(e)}")
        traceback.print_exc()
        return None, None

def load_dataset_with_mapping(config):
    """
    Load dataset from Hugging Face or local files and apply necessary transformations.
    
    Args:
        config (dict): Dataset configuration dictionary
    
    Returns:
        Dataset: The loaded and processed dataset
    """
    # Extract dataset configuration
    dataset_info = get_config_value(config, "dataset", {})
    dataset_name = get_config_value(dataset_info, "name", None)
    dataset_split = get_config_value(dataset_info, "split", "train")
    
    # Data formatting configuration
    formatting_config = get_config_value(config, "data_formatting", {})
    
    if not dataset_name:
        raise ValueError("Dataset name not specified in config")
    
    log_info(f"Loading dataset: {dataset_name} (split: {dataset_split})")
    
    try:
        # Load dataset from Hugging Face or local path
        from datasets import load_dataset
        
        # Check if it's a local path or Hugging Face dataset
        if os.path.exists(dataset_name) or os.path.exists(os.path.join(os.getcwd(), dataset_name)):
            log_info(f"Loading dataset from local path: {dataset_name}")
            # Local dataset - check if it's a directory or file
            if os.path.isdir(dataset_name):
                # Directory - look for data files
                dataset = load_dataset(
                    "json", 
                    data_files={"train": os.path.join(dataset_name, "*.json")},
                    split=dataset_split
                )
            else:
                # Single file
                dataset = load_dataset(
                    "json",
                    data_files={"train": dataset_name},
                    split=dataset_split
                )
        else:
            # Hugging Face dataset
            log_info(f"Loading dataset from Hugging Face: {dataset_name}")
            dataset = load_dataset(dataset_name, split=dataset_split)
        
        log_info(f"Dataset loaded with {len(dataset)} examples")
        
        # Check if dataset contains required fields
        required_fields = ["conversations"]
        missing_fields = [field for field in required_fields if field not in dataset.column_names]
        
        if missing_fields:
            log_info(f"WARNING: Dataset missing required fields: {missing_fields}")
            log_info("Attempting to map dataset structure to required format")
            
            # Implement conversion logic based on dataset structure
            if "messages" in dataset.column_names:
                log_info("Converting 'messages' field to 'conversations' format")
                dataset = dataset.map(
                    lambda x: {"conversations": x["messages"]},
                    remove_columns=["messages"]
                )
            elif "text" in dataset.column_names:
                log_info("Converting plain text to conversations format")
                dataset = dataset.map(
                    lambda x: {"conversations": [{"role": "user", "content": x["text"]}]},
                    remove_columns=["text"]
                )
            else:
                raise ValueError(f"Cannot convert dataset format - missing required fields and no conversion path available")
        
        # Log dataset info
        log_info(f"Dataset has {len(dataset)} examples and columns: {dataset.column_names}")
        
        # Show a few examples for verification
        for i in range(min(3, len(dataset))):
            example = dataset[i]
            log_info(f"Example {i}:")
            for key, value in example.items():
                if key == "conversations":
                    log_info(f"  conversations: {len(value)} messages")
                    # Show first message only to avoid cluttering logs
                    if value and len(value) > 0:
                        first_msg = value[0]
                        if isinstance(first_msg, dict) and "content" in first_msg:
                            content = first_msg["content"]
                            log_info(f"  First message: {content[:50]}..." if len(content) > 50 else f"  First message: {content}")
                else:
                    log_info(f"  {key}: {value}")
        
        return dataset
        
    except Exception as e:
        log_info(f"Error loading dataset: {str(e)}")
        traceback.print_exc()
        return None

def format_phi_chat(messages, dataset_config):
    """Format messages according to phi-4's chat template and dataset config.
    Only formats the conversation structure, preserves the actual content."""
    formatted_chat = ""
    
    # Get role templates from config
    roles = dataset_config.get("data_formatting", {}).get("roles", {
        "system": "System: {content}\n\n",
        "human": "Human: {content}\n\n",
        "assistant": "Assistant: {content}\n\n"
    })
    
    # Handle each message in the conversation
    for message in messages:
        if not isinstance(message, dict) or "content" not in message:
            logger.warning(f"Skipping invalid message format: {message}")
            continue
            
        content = message.get("content", "")  # Don't strip() - preserve exact content
        
        # Skip empty content
        if not content:
            continue
            
        # Only add role prefixes based on position/content
        if "[RESEARCH INTRODUCTION]" in content:
            # System message
            template = roles.get("system", "System: {content}\n\n")
            formatted_chat = template.format(content=content) + formatted_chat
        else:
            # Alternate between human and assistant for regular conversation turns
            # In phi-4 format, human messages come first, followed by assistant responses
            if len(formatted_chat.split("Human:")) == len(formatted_chat.split("Assistant:")):
                # If equal numbers of Human and Assistant messages, next is Human
                template = roles.get("human", "Human: {content}\n\n")
            else:
                # Otherwise, next is Assistant
                template = roles.get("assistant", "Assistant: {content}\n\n")
            formatted_chat += template.format(content=content)
    
    return formatted_chat

class SimpleDataCollator:
    def __init__(self, tokenizer, dataset_config):
        self.tokenizer = tokenizer
        self.max_seq_length = min(dataset_config.get("max_seq_length", 2048), tokenizer.model_max_length)
        self.stats = {
            "processed": 0,
            "skipped": 0,
            "total_tokens": 0
        }
        logger.info(f"Initialized SimpleDataCollator with max_seq_length={self.max_seq_length}")

    def __call__(self, features):
        # Initialize tensors on CPU to save GPU memory
        batch = {
            "input_ids": [],
            "attention_mask": [],
            "labels": []
        }
        
        for feature in features:
            paper_id = feature.get("article_id", "unknown")
            prompt_num = feature.get("prompt_number", 0)
            conversations = feature.get("conversations", [])
            
            if not conversations:
                logger.warning(f"No conversations for paper_id {paper_id}, prompt {prompt_num}")
                self.stats["skipped"] += 1
                continue
                
            # Get the content directly
            content = conversations[0].get("content", "")
            if not content:
                logger.warning(f"Empty content for paper_id {paper_id}, prompt {prompt_num}")
                self.stats["skipped"] += 1
                continue
            
            # Process the content string by tokenizing it
            if isinstance(content, str):
                # Tokenize the content string
                input_ids = self.tokenizer.encode(content, add_special_tokens=True)
            else:
                # If somehow the content is already tokenized (not a string), use it directly
                input_ids = content
            
            # Truncate if needed
            if len(input_ids) > self.max_seq_length:
                input_ids = input_ids[:self.max_seq_length]
                logger.warning(f"Truncated sequence for paper_id {paper_id}, prompt {prompt_num}")
            
            # Create attention mask (1s for all tokens)
            attention_mask = [1] * len(input_ids)
            
            # Add to batch
            batch["input_ids"].append(input_ids)
            batch["attention_mask"].append(attention_mask)
            batch["labels"].append(input_ids.copy())  # For causal LM, labels = input_ids
            
            self.stats["processed"] += 1
            self.stats["total_tokens"] += len(input_ids)
            
        # Log statistics periodically
        if self.stats["processed"] % 100 == 0:
            avg_tokens = self.stats["total_tokens"] / max(1, self.stats["processed"])
            logger.info(f"Data collation stats: processed={self.stats['processed']}, "
                       f"skipped={self.stats['skipped']}, avg_tokens={avg_tokens:.1f}")
        
        # Convert to tensors or pad sequences (PyTorch will handle)
        if batch["input_ids"]:
            # Pad sequences to max length in batch using the tokenizer
            batch = self.tokenizer.pad(
                batch,
                padding="max_length",
                max_length=self.max_seq_length,
                return_tensors="pt"
            )
            return batch
        else:
            # Return empty batch if no valid examples
            return {k: [] for k in batch}

def log_gpu_memory_usage(step=None, frequency=50, clear_cache_threshold=0.9, label=None):
    """
    Log GPU memory usage statistics with optional cache clearing
    
    Args:
        step: Current training step (if None, logs regardless of frequency)
        frequency: How often to log when step is provided
        clear_cache_threshold: Fraction of memory used that triggers cache clearing (0-1)
        label: Optional label for the log message (e.g., "Initial", "Error", "Step")
    """
    if not CUDA_AVAILABLE:
        return
    
    # Only log every 'frequency' steps if step is provided
    if step is not None and frequency > 0 and step % frequency != 0:
        return
        
    # Get memory usage for each GPU
    memory_info = []
    for i in range(NUM_GPUS):
        allocated = torch.cuda.memory_allocated(i) / (1024 ** 2)  # MB
        reserved = torch.cuda.memory_reserved(i) / (1024 ** 2)    # MB
        max_mem = torch.cuda.max_memory_allocated(i) / (1024 ** 2) # MB
        
        # Calculate percentage of reserved memory that's allocated
        usage_percent = (allocated / reserved) * 100 if reserved > 0 else 0
        memory_info.append(f"GPU {i}: {allocated:.1f}MB/{reserved:.1f}MB ({usage_percent:.1f}%, max: {max_mem:.1f}MB)")
        
        # Automatically clear cache if over threshold
        if clear_cache_threshold > 0 and reserved > 0 and (allocated / reserved) > clear_cache_threshold:
            log_info(f"Clearing CUDA cache for GPU {i} - high utilization ({allocated:.1f}/{reserved:.1f}MB)")
            with torch.cuda.device(i):
                torch.cuda.empty_cache()
    
    prefix = f"{label} " if label else ""
    log_info(f"{prefix}GPU Memory: {', '.join(memory_info)}")

class LoggingCallback(TrainerCallback):
    """
    Custom callback for logging training progress and metrics.
    Provides detailed information about training status, GPU memory usage, and model performance.
    """
    def __init__(self, model=None, dataset=None):
        # Ensure we have TrainerCallback
        try:
            super().__init__()
        except Exception as e:
            # Try to import directly if initial import failed
            try:
                from transformers.trainer_callback import TrainerCallback
                self.__class__.__bases__ = (TrainerCallback,)
                super().__init__()
                log_info("Successfully imported TrainerCallback directly")
            except ImportError as ie:
                log_info(f"❌ Error: Could not import TrainerCallback: {str(ie)}")
                log_info("Please ensure transformers is properly installed")
                raise
        
        self.training_started = time.time()
        self.last_log_time = time.time()
        self.last_step_time = None
        self.step_durations = []
        self.best_loss = float('inf')
        self.model = model
        self.dataset = dataset
        
    def on_train_begin(self, args, state, control, **kwargs):
        """Called at the beginning of training"""
        try:
            log_info(f"=== Training started at {time.strftime('%Y-%m-%d %H:%M:%S')} ===")
            
            # Log model info if available
            if self.model is not None:
                total_params = sum(p.numel() for p in self.model.parameters())
                trainable_params = sum(p.numel() for p in self.model.parameters() if p.requires_grad)
                log_info(f"Model parameters: {total_params/1e6:.2f}M total, {trainable_params/1e6:.2f}M trainable")
                
            # Log dataset info if available
            if self.dataset is not None:
                log_info(f"Dataset size: {len(self.dataset)} examples")
            
            # Log important training parameters for visibility
            total_batch_size = args.per_device_train_batch_size * args.gradient_accumulation_steps * NUM_GPUS
            total_steps = int(len(self.dataset or []) / (args.per_device_train_batch_size * NUM_GPUS * args.gradient_accumulation_steps) * args.num_train_epochs)
            log_info(f"Training plan: {len(self.dataset or [])} examples over {args.num_train_epochs} epochs ≈ {total_steps} steps")
            log_info(f"Batch size: {args.per_device_train_batch_size} × {args.gradient_accumulation_steps} steps × {NUM_GPUS} GPUs = {total_batch_size} total")
            
            # Log initial GPU memory usage with label
            log_gpu_memory_usage(label="Initial")
        except Exception as e:
            logger.warning(f"Error logging training begin statistics: {str(e)}")
    
    def on_step_end(self, args, state, control, **kwargs):
        """Called at the end of each step"""
        try:
            if state.global_step == 1 or state.global_step % args.logging_steps == 0:
                # Track step timing
                current_time = time.time()
                if self.last_step_time:
                    step_duration = current_time - self.last_step_time
                    self.step_durations.append(step_duration)
                    # Keep only last 100 steps for averaging
                    if len(self.step_durations) > 100:
                        self.step_durations.pop(0)
                    avg_step_time = sum(self.step_durations) / len(self.step_durations)
                    log_info(f"Step {state.global_step}: {step_duration:.2f}s (avg: {avg_step_time:.2f}s)")
                
                self.last_step_time = current_time
                
                # Log GPU memory usage with step number
                log_gpu_memory_usage(state.global_step, args.logging_steps)
                
                # Log loss
                if state.log_history:
                    latest_logs = state.log_history[-1] if state.log_history else {}
                    if "loss" in latest_logs:
                        loss = latest_logs["loss"]
                        log_info(f"Step {state.global_step} loss: {loss:.4f}")
                        
                        # Track best loss
                        if loss < self.best_loss:
                            self.best_loss = loss
                            log_info(f"New best loss: {loss:.4f}")
        except Exception as e:
            logger.warning(f"Error logging step end statistics: {str(e)}")
    
    def on_train_end(self, args, state, control, **kwargs):
        """Called at the end of training"""
        try:
            # Calculate training duration
            training_time = time.time() - self.training_started
            hours, remainder = divmod(training_time, 3600)
            minutes, seconds = divmod(remainder, 60)
            
            log_info(f"=== Training completed at {time.strftime('%Y-%m-%d %H:%M:%S')} ===")
            log_info(f"Training duration: {int(hours)}h {int(minutes)}m {int(seconds)}s")
            log_info(f"Final step: {state.global_step}")
            log_info(f"Best loss: {self.best_loss:.4f}")
            
            # Log final GPU memory usage
            log_gpu_memory_usage(label="Final")
        except Exception as e:
            logger.warning(f"Error logging training end statistics: {str(e)}")
            
    # Other callback methods with proper error handling
    def on_save(self, args, state, control, **kwargs):
        """Called when a checkpoint is saved"""
        try:
            log_info(f"Saving checkpoint at step {state.global_step}")
        except Exception as e:
            logger.warning(f"Error in on_save: {str(e)}")
    
    def on_log(self, args, state, control, **kwargs):
        """Called when a log is created"""
        pass
        
    def on_evaluate(self, args, state, control, **kwargs):
        """Called when evaluation is performed"""
        pass
        
    # Only implement the methods we actually need, remove the others
    def on_prediction_step(self, args, state, control, **kwargs):
        """Called when prediction is performed"""
        pass
    
    def on_save_model(self, args, state, control, **kwargs):
        """Called when model is saved"""
        try:
            # Log memory usage after saving
            log_gpu_memory_usage(label=f"Save at step {state.global_step}")
        except Exception as e:
            logger.warning(f"Error in on_save_model: {str(e)}")
    
    def on_epoch_end(self, args, state, control, **kwargs):
        """Called at the end of an epoch"""
        try:
            epoch = state.epoch
            log_info(f"Completed epoch {epoch:.2f}")
            log_gpu_memory_usage(label=f"Epoch {epoch:.2f}")
        except Exception as e:
            logger.warning(f"Error in on_epoch_end: {str(e)}")
    
    def on_step_begin(self, args, state, control, **kwargs):
        """Called at the beginning of a step"""
        pass

def install_flash_attention():
    """
    Attempt to install Flash Attention for improved performance.
    Returns True if installation was successful, False otherwise.
    """
    log_info("Attempting to install Flash Attention...")
    
    # Check for CUDA before attempting installation
    if not CUDA_AVAILABLE:
        log_info("❌ Cannot install Flash Attention: CUDA not available")
        return False
    
    try:
        # Check CUDA version to determine correct installation command
        cuda_version = torch.version.cuda
        if cuda_version is None:
            log_info("❌ Cannot determine CUDA version for Flash Attention installation")
            return False
        
        import subprocess
        
        # Use --no-build-isolation for better compatibility
        install_cmd = [
            sys.executable, 
            "-m", 
            "pip", 
            "install", 
            "flash-attn", 
            "--no-build-isolation"
        ]
        
        log_info(f"Running: {' '.join(install_cmd)}")
        result = subprocess.run(
            install_cmd,
            capture_output=True,
            text=True,
            check=False
        )
        
        if result.returncode == 0:
            log_info("✅ Flash Attention installed successfully!")
            # Attempt to import to verify installation
            try:
                import flash_attn
                log_info(f"✅ Flash Attention version {flash_attn.__version__} is now available")
                return True
            except ImportError:
                log_info("⚠️ Flash Attention installed but import failed")
                return False
        else:
            log_info(f"❌ Flash Attention installation failed with error: {result.stderr}")
            return False
            
    except Exception as e:
        log_info(f"❌ Error installing Flash Attention: {str(e)}")
        return False

def check_dependencies():
    """
    Check for required and optional dependencies, ensuring proper versions and import order.
    Returns True if all required dependencies are present, False otherwise.
    """
    # Define required packages with versions and descriptions
    required_packages = {
        "unsloth": {"version": ">=2024.3", "feature": "fast 4-bit quantization and LoRA"},
        "transformers": {"version": ">=4.38.0", "feature": "core model functionality"},
        "peft": {"version": ">=0.9.0", "feature": "parameter-efficient fine-tuning"},
        "accelerate": {"version": ">=0.27.0", "feature": "multi-GPU training"}
    }
    
    # Optional packages that enhance functionality
    optional_packages = {
        "flash_attn": {"feature": "faster attention computation"},
        "bitsandbytes": {"feature": "quantization support"},
        "optimum": {"feature": "model optimization"},
        "wandb": {"feature": "experiment tracking"}
    }
    
    # Store results
    missing_packages = []
    package_versions = {}
    order_issues = []
    missing_optional = []
    
    # Check required packages
    log_info("Checking required dependencies...")
    for package, info in required_packages.items():
        version_req = info["version"]
        feature = info["feature"]
        
        try:
            # Special handling for packages we've already checked
            if package == "unsloth" and not unsloth_available:
                missing_packages.append(f"{package}{version_req}")
                log_info(f"❌ {package} - {feature} MISSING")
                continue
            elif package == "peft" and not peft_available:
                missing_packages.append(f"{package}{version_req}")
                log_info(f"❌ {package} - {feature} MISSING")
                continue
                
            # Try to import and get version
            module = __import__(package)
            version = getattr(module, "__version__", "unknown")
            package_versions[package] = version
            log_info(f"✅ {package} v{version} - {feature}")
            
        except ImportError:
            missing_packages.append(f"{package}{version_req}")
            log_info(f"❌ {package} - {feature} MISSING")
    
    # Check optional packages
    log_info("\nChecking optional dependencies...")
    for package, info in optional_packages.items():
        feature = info["feature"]
        try:
            __import__(package)
            log_info(f"✅ {package} - {feature} available")
        except ImportError:
            log_info(f"⚠️ {package} - {feature} not available")
            missing_optional.append(package)
    
    # Check import order for optimal performance
    if "transformers" in package_versions and "unsloth" in package_versions:
        try:
            import sys
            modules = list(sys.modules.keys())
            transformers_idx = modules.index("transformers")
            unsloth_idx = modules.index("unsloth")
            
            if transformers_idx < unsloth_idx:
                order_issue = "⚠️ For optimal performance, import unsloth before transformers"
                order_issues.append(order_issue)
                log_info(order_issue)
                log_info("This might cause performance issues but won't prevent training")
            else:
                log_info("✅ Import order: unsloth before transformers (optimal)")
        except (ValueError, IndexError) as e:
            log_info(f"⚠️ Could not verify import order: {str(e)}")
    
    # Try to install missing optional packages
    if "flash_attn" in missing_optional and CUDA_AVAILABLE:
        log_info("\nFlash Attention is missing but would improve performance.")
        install_result = install_flash_attention()
        if install_result:
            missing_optional.remove("flash_attn")
    
    # Report missing required packages
    if missing_packages:
        log_info("\n❌ Critical dependencies missing:")
        for pkg in missing_packages:
            log_info(f"  - {pkg}")
        log_info("Please install missing dependencies with:")
        log_info(f"  pip install {' '.join(missing_packages)}")
        return False
    
    log_info("\n✅ All required dependencies satisfied!")
    return True

def get_config_value(config, path, default=None):
    """
    Safely get a nested value from a config dictionary using a dot-separated path.
    
    Args:
        config: The configuration dictionary
        path: Dot-separated path to the value (e.g., "training.optimizer.lr")
        default: Default value to return if path doesn't exist
        
    Returns:
        The value at the specified path or the default value
    """
    if not config:
        return default
        
    parts = path.split('.')
    current = config
    
    for part in parts:
        if isinstance(current, dict) and part in current:
            current = current[part]
        else:
            return default
            
    return current

def update_huggingface_space():
    """Update the Hugging Face Space with the current code."""
    log_info("Updating Hugging Face Space...")
    update_script = os.path.join(os.path.dirname(os.path.abspath(__file__)), "update_space.py")
    
    if not os.path.exists(update_script):
        logger.warning(f"Update space script not found at {update_script}")
        return False
    
    try:
        import subprocess
        # Explicitly set space_name to ensure we're targeting the right Space
        result = subprocess.run(
            [sys.executable, update_script, "--force", "--space_name", "phi4training"], 
            capture_output=True, text=True, check=False
        )
        
        if result.returncode == 0:
            log_info("Hugging Face Space updated successfully!")
            log_info(f"Space URL: https://huggingface.co/spaces/George-API/phi4training")
            return True
        else:
            logger.error(f"Failed to update Hugging Face Space: {result.stderr}")
            return False
    except Exception as e:
        logger.error(f"Error updating Hugging Face Space: {str(e)}")
        return False

def validate_huggingface_credentials():
    """Validate Hugging Face credentials to ensure they work correctly."""
    if not os.environ.get("HF_TOKEN"):
        logger.warning("HF_TOKEN not found. Skipping Hugging Face credentials validation.")
        return False
    
    try:
        # Import here to avoid requiring huggingface_hub if not needed
        from huggingface_hub import HfApi, login
        
        # Try to login with the token
        login(token=os.environ.get("HF_TOKEN"))
        
        # Check if we can access the API
        api = HfApi()
        username = os.environ.get("HF_USERNAME", "George-API")
        space_name = os.environ.get("HF_SPACE_NAME", "phi4training")
        
        # Try to get whoami info
        user_info = api.whoami()
        logger.info(f"Successfully authenticated with Hugging Face as {user_info['name']}")
        
        # Check if we're using the expected Space
        expected_space_id = "George-API/phi4training"
        actual_space_id = f"{username}/{space_name}"
        
        if actual_space_id != expected_space_id:
            logger.warning(f"Using Space '{actual_space_id}' instead of the expected '{expected_space_id}'")
            logger.warning(f"Make sure this is intentional. To use the correct Space, update your .env file.")
        else:
            logger.info(f"Confirmed using Space: {expected_space_id}")
        
        # Check if the space exists
        try:
            space_id = f"{username}/{space_name}"
            space_info = api.space_info(repo_id=space_id)
            logger.info(f"Space {space_id} is accessible at: https://huggingface.co/spaces/{space_id}")
            return True
        except Exception as e:
            logger.warning(f"Could not access Space {username}/{space_name}: {str(e)}")
            logger.warning("Space updating may not work correctly")
            return False
    except ImportError:
        logger.warning("huggingface_hub not installed. Cannot validate Hugging Face credentials.")
        return False
    except Exception as e:
        logger.warning(f"Error validating Hugging Face credentials: {str(e)}")
        return False

def setup_environment(args):
    """
    Set up the training environment including logging, seed, and configurations.
    
    Args:
        args: Command line arguments
    
    Returns:
        tuple: (transformers_config, seed) - The loaded configuration and random seed
    """
    # Load environment variables first
    load_env_variables()
    
    # Set random seed for reproducibility
    seed = args.seed if args.seed is not None else int(time.time()) % 10000
    set_seed(seed)
    log_info(f"Using random seed: {seed}")
    
    # Load configuration
    base_path = os.path.dirname(os.path.abspath(__file__))
    config_file = args.config_file or os.path.join(base_path, "transformers_config.json")
    
    if not os.path.exists(config_file):
        raise FileNotFoundError(f"Config file not found: {config_file}")
        
    log_info(f"Loading configuration from {config_file}")
    transformers_config = load_configs(config_file)
    
    # Set up hardware environment variables if CUDA is available
    if CUDA_AVAILABLE:
        memory_fraction = get_config_value(transformers_config, "hardware.system_settings.cuda_memory_fraction", 0.75)
        if memory_fraction < 1.0:
            os.environ["PYTORCH_CUDA_ALLOC_CONF"] = f"max_split_size_mb:128,expandable_segments:True"
            log_info(f"Set CUDA memory allocation limit to expandable with max_split_size_mb:128")
    
    # Check dependencies and install optional ones if needed
    if not check_dependencies():
        raise RuntimeError("Critical dependencies missing")
    
    # Check if flash attention was successfully installed
    flash_attention_available = False
    try:
        import flash_attn
        flash_attention_available = True
        log_info(f"Flash Attention will be used (version: {flash_attn.__version__})")
        # Update config to use flash attention
        if "use_flash_attention" not in transformers_config:
            transformers_config["use_flash_attention"] = True
    except ImportError:
        log_info("Flash Attention not available, will use standard attention mechanism")
        
    return transformers_config, seed

def setup_model_and_tokenizer(config):
    """
    Load and configure the model and tokenizer.
    
    Args:
        config (dict): Complete configuration dictionary
    
    Returns:
        tuple: (model, tokenizer) - The loaded model and tokenizer
    """
    # Extract model configuration
    model_config = get_config_value(config, "model", {})
    model_name = get_config_value(model_config, "name", "unsloth/phi-4-unsloth-bnb-4bit")
    use_fast_tokenizer = get_config_value(model_config, "use_fast_tokenizer", True)
    trust_remote_code = get_config_value(model_config, "trust_remote_code", True)
    model_revision = get_config_value(config, "model_revision", "main")
    
    # Detect if model is already pre-quantized (includes '4bit', 'bnb', or 'int4' in name)
    is_prequantized = any(q in model_name.lower() for q in ['4bit', 'bnb', 'int4', 'quant'])
    if is_prequantized:
        log_info("⚠️ Detected pre-quantized model. No additional quantization will be applied.")
    
    # Unsloth configuration
    unsloth_config = get_config_value(config, "unsloth", {})
    unsloth_enabled = get_config_value(unsloth_config, "enabled", True)
    
    # Tokenizer configuration
    tokenizer_config = get_config_value(config, "tokenizer", {})
    max_seq_length = min(
        get_config_value(tokenizer_config, "max_seq_length", 2048),
        4096  # Maximum supported by most models
    )
    add_eos_token = get_config_value(tokenizer_config, "add_eos_token", True)
    chat_template = get_config_value(tokenizer_config, "chat_template", None)
    padding_side = get_config_value(tokenizer_config, "padding_side", "right")
    
    # Check for flash attention
    use_flash_attention = get_config_value(config, "use_flash_attention", False)
    flash_attention_available = False
    try:
        import flash_attn
        flash_attention_available = True
        log_info(f"Flash Attention detected (version: {flash_attn.__version__})")
    except ImportError:
        if use_flash_attention:
            log_info("Flash Attention requested but not available")
    
    log_info(f"Loading model: {model_name} (revision: {model_revision})")
    log_info(f"Max sequence length: {max_seq_length}")
    
    try:
        if unsloth_enabled and unsloth_available:
            log_info("Using Unsloth for LoRA fine-tuning")
            if is_prequantized:
                log_info("Using pre-quantized model - no additional quantization will be applied")
            else:
                log_info("Using 4-bit quantization for efficient training")
                
            # Load using Unsloth
            from unsloth import FastLanguageModel
            model, tokenizer = FastLanguageModel.from_pretrained(
                model_name=model_name,
                max_seq_length=max_seq_length,
                dtype=get_config_value(config, "torch_dtype", "bfloat16"),
                revision=model_revision,
                trust_remote_code=trust_remote_code,
                use_flash_attention_2=use_flash_attention and flash_attention_available
            )
            
            # Configure tokenizer settings
            tokenizer.padding_side = padding_side
            if add_eos_token and tokenizer.eos_token is None:
                log_info("Setting EOS token")
                tokenizer.add_special_tokens({"eos_token": "</s>"})
            
            # Set chat template if specified
            if chat_template:
                log_info(f"Setting chat template: {chat_template}")
                if hasattr(tokenizer, "chat_template"):
                    tokenizer.chat_template = chat_template
                else:
                    log_info("Tokenizer does not support chat templates, using default formatting")
            
            # Apply LoRA
            lora_r = get_config_value(unsloth_config, "r", 16)
            lora_alpha = get_config_value(unsloth_config, "alpha", 32)
            lora_dropout = get_config_value(unsloth_config, "dropout", 0)
            target_modules = get_config_value(unsloth_config, "target_modules", 
                ["q_proj", "k_proj", "v_proj", "o_proj", "gate_proj", "up_proj", "down_proj"])
            
            log_info(f"Applying LoRA with r={lora_r}, alpha={lora_alpha}, dropout={lora_dropout}")
            model = FastLanguageModel.get_peft_model(
                model,
                r=lora_r,
                target_modules=target_modules,
                lora_alpha=lora_alpha,
                lora_dropout=lora_dropout,
                bias="none",
                use_gradient_checkpointing=get_config_value(config, "training.gradient_checkpointing", True),
                random_state=0,
                max_seq_length=max_seq_length,
                modules_to_save=None
            )
            
            if use_flash_attention and flash_attention_available:
                log_info("🚀 Using Flash Attention for faster training")
            elif use_flash_attention and not flash_attention_available:
                log_info("⚠️ Flash Attention requested but not available - using standard attention")
                
        else:
            # Standard HuggingFace loading
            log_info("Using standard HuggingFace model loading (Unsloth not available or disabled)")
            from transformers import AutoModelForCausalLM, AutoTokenizer
            
            # Check if flash attention should be enabled in config
            use_attn_implementation = None
            if use_flash_attention and flash_attention_available:
                use_attn_implementation = "flash_attention_2"
                log_info("🚀 Using Flash Attention for faster training")
            
            # Load tokenizer first
            tokenizer = AutoTokenizer.from_pretrained(
                model_name,
                trust_remote_code=trust_remote_code,
                use_fast=use_fast_tokenizer,
                revision=model_revision,
                padding_side=padding_side
            )
            
            # Configure tokenizer settings
            if add_eos_token and tokenizer.eos_token is None:
                log_info("Setting EOS token")
                tokenizer.add_special_tokens({"eos_token": "</s>"})
            
            # Set chat template if specified
            if chat_template:
                log_info(f"Setting chat template: {chat_template}")
                if hasattr(tokenizer, "chat_template"):
                    tokenizer.chat_template = chat_template
                else:
                    log_info("Tokenizer does not support chat templates, using default formatting")
            
            # Only apply quantization config if model is not already pre-quantized
            quantization_config = None
            if not is_prequantized and CUDA_AVAILABLE:
                try:
                    from transformers import BitsAndBytesConfig
                    log_info("Using 4-bit quantization (BitsAndBytes) for efficient training")
                    quantization_config = BitsAndBytesConfig(
                        load_in_4bit=True,
                        bnb_4bit_quant_type="nf4",
                        bnb_4bit_compute_dtype=torch.float16,
                        bnb_4bit_use_double_quant=True
                    )
                except ImportError:
                    log_info("BitsAndBytes not available - quantization disabled")
            
            # Now load model with updated tokenizer
            model = AutoModelForCausalLM.from_pretrained(
                model_name,
                trust_remote_code=trust_remote_code,
                revision=model_revision,
                torch_dtype=torch.bfloat16 if get_config_value(config, "torch_dtype", "bfloat16") == "bfloat16" else torch.float16,
                device_map="auto" if CUDA_AVAILABLE else None,
                attn_implementation=use_attn_implementation,
                quantization_config=quantization_config
            )
            
            # Apply PEFT/LoRA if enabled but using standard loading
            if peft_available and get_config_value(unsloth_config, "enabled", True):
                log_info("Applying standard PEFT/LoRA configuration")
                from peft import LoraConfig, get_peft_model
                
                lora_r = get_config_value(unsloth_config, "r", 16)
                lora_alpha = get_config_value(unsloth_config, "alpha", 32)
                lora_dropout = get_config_value(unsloth_config, "dropout", 0)
                target_modules = get_config_value(unsloth_config, "target_modules", 
                    ["q_proj", "k_proj", "v_proj", "o_proj", "gate_proj", "up_proj", "down_proj"])
                
                log_info(f"Applying LoRA with r={lora_r}, alpha={lora_alpha}, dropout={lora_dropout}")
                lora_config = LoraConfig(
                    r=lora_r,
                    lora_alpha=lora_alpha,
                    target_modules=target_modules,
                    lora_dropout=lora_dropout,
                    bias="none",
                    task_type="CAUSAL_LM"
                )
                model = get_peft_model(model, lora_config)
        
        # Print model summary
        log_info(f"Model loaded successfully: {model.__class__.__name__}")
        if hasattr(model, "print_trainable_parameters"):
            model.print_trainable_parameters()
        else:
            total_params = sum(p.numel() for p in model.parameters())
            trainable_params = sum(p.numel() for p in model.parameters() if p.requires_grad)
            log_info(f"Model has {total_params:,} parameters, {trainable_params:,} trainable ({trainable_params/total_params:.2%})")
        
        return model, tokenizer
        
    except Exception as e:
        log_info(f"Error loading model: {str(e)}")
        traceback.print_exc()
        return None, None

def setup_dataset_and_collator(config, tokenizer):
    """
    Load and configure the dataset and data collator.
    
    Args:
        config: Complete configuration dictionary
        tokenizer: The tokenizer for the data collator
    
    Returns:
        tuple: (dataset, data_collator) - The loaded dataset and configured data collator
    """
    dataset_config = get_config_value(config, "dataset", {})
    
    log_info("Loading dataset...")
    dataset = load_dataset_with_mapping(dataset_config)
    
    # Validate dataset
    if dataset is None:
        raise ValueError("Dataset is None! Cannot proceed with training.")
        
    if not hasattr(dataset, '__len__') or len(dataset) == 0:
        raise ValueError("Dataset is empty! Cannot proceed with training.")
        
    log_info(f"Dataset loaded with {len(dataset)} examples")
    
    # Create data collator
    data_collator = SimpleDataCollator(tokenizer, dataset_config)
    
    return dataset, data_collator

def create_training_arguments(config, dataset):
    """
    Create and configure training arguments for the Trainer.
    
    Args:
        config: Complete configuration dictionary
        dataset: The dataset to determine total steps
    
    Returns:
        TrainingArguments: Configured training arguments
    """
    # Extract configuration sections
    training_config = get_config_value(config, "training", {})
    hardware_config = get_config_value(config, "hardware", {})
    huggingface_config = get_config_value(config, "huggingface_hub", {})
    distributed_config = get_config_value(config, "distributed_training", {})
    
    # Extract key training parameters
    per_device_batch_size = get_config_value(training_config, "per_device_train_batch_size", 4)
    gradient_accumulation_steps = get_config_value(training_config, "gradient_accumulation_steps", 8)
    learning_rate = get_config_value(training_config, "learning_rate", 2e-5)
    num_train_epochs = get_config_value(training_config, "num_train_epochs", 3)
    
    # Extract hardware settings
    dataloader_workers = get_config_value(hardware_config, "system_settings.dataloader_num_workers", 
                                     get_config_value(distributed_config, "dataloader_num_workers", 2))
    pin_memory = get_config_value(hardware_config, "system_settings.dataloader_pin_memory", True)
    
    # BF16/FP16 settings - ensure only one is enabled
    use_bf16 = get_config_value(training_config, "bf16", False)
    use_fp16 = get_config_value(training_config, "fp16", False) if not use_bf16 else False
    
    # Configure distributed training
    fsdp_config = get_config_value(distributed_config, "fsdp_config", {})
    fsdp_enabled = get_config_value(fsdp_config, "enabled", False)
    
    ddp_config = get_config_value(distributed_config, "ddp_config", {})
    ddp_find_unused_parameters = get_config_value(ddp_config, "find_unused_parameters", False)
    
    # Set up FSDP args if enabled
    fsdp_args = None
    if fsdp_enabled and NUM_GPUS > 1:
        from accelerate import FullyShardedDataParallelPlugin
        from torch.distributed.fsdp.fully_sharded_data_parallel import (
            FullOptimStateDictConfig, FullStateDictConfig
        )
        
        fsdp_plugin = FullyShardedDataParallelPlugin(
            sharding_strategy=get_config_value(fsdp_config, "sharding_strategy", "FULL_SHARD"),
            mixed_precision_policy=get_config_value(fsdp_config, "mixed_precision", "BF16"),
            state_dict_config=FullStateDictConfig(offload_to_cpu=True, rank0_only=True),
            optim_state_dict_config=FullOptimStateDictConfig(offload_to_cpu=True, rank0_only=True),
        )
        
        fsdp_args = {
            "fsdp": fsdp_plugin,
            "fsdp_transformer_layer_cls_to_wrap": ["LlamaDecoderLayer", "PhiDecoderLayer"]
        }
    
    # Create and return training arguments
    training_args = TrainingArguments(
        output_dir=get_config_value(config, "checkpointing.output_dir", "./results"),
        overwrite_output_dir=True,
        num_train_epochs=num_train_epochs,
        per_device_train_batch_size=per_device_batch_size,
        gradient_accumulation_steps=gradient_accumulation_steps,
        learning_rate=learning_rate,
        weight_decay=get_config_value(training_config, "weight_decay", 0.01),
        max_grad_norm=get_config_value(training_config, "max_grad_norm", 1.0),
        warmup_ratio=get_config_value(training_config, "warmup_ratio", 0.03),
        lr_scheduler_type=get_config_value(training_config, "lr_scheduler_type", "cosine"),
        logging_steps=get_config_value(training_config, "logging_steps", 10),
        save_strategy=get_config_value(config, "checkpointing.save_strategy", "steps"),
        save_steps=get_config_value(config, "checkpointing.save_steps", 500),
        save_total_limit=get_config_value(config, "checkpointing.save_total_limit", 3),
        bf16=use_bf16,
        fp16=use_fp16,
        push_to_hub=get_config_value(huggingface_config, "push_to_hub", False),
        hub_model_id=get_config_value(huggingface_config, "hub_model_id", None),
        hub_strategy=get_config_value(huggingface_config, "hub_strategy", "every_save"),
        hub_private_repo=get_config_value(huggingface_config, "hub_private_repo", True),
        gradient_checkpointing=get_config_value(training_config, "gradient_checkpointing", True),
        dataloader_pin_memory=pin_memory,
        optim=get_config_value(training_config, "optim", "adamw_torch"),
        ddp_find_unused_parameters=ddp_find_unused_parameters,
        dataloader_drop_last=False,
        dataloader_num_workers=dataloader_workers,
        no_cuda=False if CUDA_AVAILABLE else True,
        **({} if fsdp_args is None else fsdp_args)
    )

    log_info("Training arguments created successfully")
    return training_args

def configure_custom_dataloader(trainer, dataset, config, training_args):
    """
    Configure a custom dataloader for the trainer if needed.
    
    Args:
        trainer: The Trainer instance to configure
        dataset: The dataset to use
        config: Complete configuration dictionary
        training_args: The training arguments
        
    Returns:
        None (modifies trainer in-place)
    """
    dataset_config = get_config_value(config, "dataset", {})
    
    # Check if we need a custom dataloader
    if get_config_value(dataset_config, "data_loading.sequential_processing", True):
        log_info("Using custom sequential dataloader")
        
        # Create sequential sampler to maintain dataset order
        sequential_sampler = torch.utils.data.SequentialSampler(dataset)
        log_info("Sequential sampler created")
        
        # Define custom dataloader getter
        def custom_get_train_dataloader():
            """Create a custom dataloader that maintains dataset order"""
            # Get configuration values
            batch_size = training_args.per_device_train_batch_size
            drop_last = get_config_value(dataset_config, "data_loading.drop_last", False)
            num_workers = training_args.dataloader_num_workers
            pin_memory = training_args.dataloader_pin_memory
            prefetch_factor = get_config_value(dataset_config, "data_loading.prefetch_factor", 2)
            persistent_workers = get_config_value(dataset_config, "data_loading.persistent_workers", False)
            
            # Create DataLoader with sequential sampler
            return DataLoader(
                dataset,
                batch_size=batch_size,
                sampler=sequential_sampler,
                collate_fn=trainer.data_collator,
                drop_last=drop_last,
                num_workers=num_workers,
                pin_memory=pin_memory,
                prefetch_factor=prefetch_factor if num_workers > 0 else None,
                persistent_workers=persistent_workers if num_workers > 0 else False,
            )
        
        # Override the default dataloader
        trainer.get_train_dataloader = custom_get_train_dataloader

def run_training(trainer, tokenizer, training_args):
    """
    Run the training process and handle model saving.
    
    Args:
        trainer: Configured Trainer instance
        tokenizer: The tokenizer to save with the model
        training_args: Training arguments
        
    Returns:
        int: 0 for success, 1 for failure
    """
    log_info("Starting training...")
    trainer.train()
    
    log_info("Training complete! Saving final model...")
    trainer.save_model()
    tokenizer.save_pretrained(training_args.output_dir)
    
    # Push to Hub if configured
    if training_args.push_to_hub:
        log_info(f"Pushing model to Hugging Face Hub: {training_args.hub_model_id}")
        trainer.push_to_hub()
        
    log_info("Training completed successfully!")
    return 0

def main():
    """
    Main entry point for the training script.
    
    Returns:
        int: 0 for success, non-zero for failure
    """
    # Set up logging
    logger.info("Starting training process")
    
    try:
        # Verify critical imports are available
        if not transformers_available:
            log_info("❌ Error: transformers library not available. Please install it with: pip install transformers")
            return 1
            
        # Check for required classes
        for required_class in ["Trainer", "TrainingArguments", "TrainerCallback"]:
            if not hasattr(transformers, required_class):
                log_info(f"❌ Error: {required_class} not found in transformers. Please update transformers.")
                return 1
        
        # Check for potential import order issue and warn early
        if "transformers" in sys.modules and "unsloth" in sys.modules:
            if list(sys.modules.keys()).index("transformers") < list(sys.modules.keys()).index("unsloth"):
                log_info("⚠️ Warning: transformers was imported before unsloth. This may affect performance.")
                log_info("   For optimal performance in future runs, import unsloth first.")
        
        # Parse command line arguments
        args = parse_args()
        
        # Set up environment and load configuration
        transformers_config, seed = setup_environment(args)
        
        # Load model and tokenizer
        try:
            model, tokenizer = setup_model_and_tokenizer(transformers_config)
        except Exception as e:
            logger.error(f"Error setting up model: {str(e)}")
            return 1
        
        # Load dataset and create data collator
        try:
            dataset, data_collator = setup_dataset_and_collator(transformers_config, tokenizer)
        except Exception as e:
            logger.error(f"Error setting up dataset: {str(e)}")
            return 1
        
        # Configure training arguments
        try:
            training_args = create_training_arguments(transformers_config, dataset)
        except Exception as e:
            logger.error(f"Error configuring training arguments: {str(e)}")
            return 1
            
        # Initialize trainer with callbacks
        log_info("Initializing Trainer")
        trainer = Trainer(
            model=model,
            args=training_args,
            train_dataset=dataset,
            data_collator=data_collator,
            callbacks=[LoggingCallback(model=model, dataset=dataset)],
        )
        
        # Configure custom dataloader if needed
        try:
            configure_custom_dataloader(trainer, dataset, transformers_config, training_args)
        except Exception as e:
            logger.error(f"Error configuring custom dataloader: {str(e)}")
            return 1
        
        # Run training process
        try:
            return run_training(trainer, tokenizer, training_args)
        except Exception as e:
            logger.error(f"Training failed with error: {str(e)}")
            # Log GPU memory for debugging
            log_gpu_memory_usage(label="Error")
            # Print full stack trace
            traceback.print_exc()
            return 1
    
    except Exception as e:
        logger.error(f"Error in main function: {str(e)}")
        traceback.print_exc()
        return 1

if __name__ == "__main__":
    sys.exit(main())