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#!/usr/bin/env python3
"""
NeuralPythonMind: small REAL neural character-level GRU trained from scratch with NumPy.

This is not a retrieval/template bot. It learns weights by next-character prediction over a
Python curriculum dataset built from:
- curated Python syntax lessons,
- generated code examples,
- local Python stdlib docstrings/signatures,
- instruction -> answer samples,
- a small strange autobiographical style layer.

Limitations:
- It is tiny and CPU-only; it will not match a transformer LLM.
- It learns statistical patterns from characters and can generalize syntax locally,
  but deep reasoning is limited.

Usage:
  python neural_python_mind.py --mode train --out outputs/neural_python_mind --steps 2500
  python neural_python_mind.py --mode generate --out outputs/neural_python_mind --prompt "### Instruction:\nWrite a Python function that counts words.\n### Answer:\n"
"""
from __future__ import annotations

import argparse
import inspect
import json
import math
import os
import random
import re
import textwrap
import time
from collections import Counter
from pathlib import Path
from typing import Dict, List, Tuple, Any

import numpy as np


# -----------------------------
# Dataset builder
# -----------------------------

MODULES_TO_SCAN = [
    "math", "random", "statistics", "itertools", "functools", "collections",
    "heapq", "bisect", "datetime", "time", "json", "csv", "re", "pathlib",
    "os", "sys", "argparse", "dataclasses", "typing", "sqlite3", "logging",
    "unittest", "string", "textwrap", "copy", "decimal", "fractions",
]

CURATED_LESSONS = r'''
### Lesson: Python identity
Python code is made of names, objects, expressions, statements, indentation, and modules.
A name can be bound to an object using assignment.
Example:
```python
x = 10
name = "Ada"
items = [1, 2, 3]
```

### Lesson: indentation
Python uses indentation to express blocks. A block belongs to the line before it ending with a colon.
Example:
```python
if score >= 60:
    print("pass")
else:
    print("fail")
```

### Lesson: functions
A function is a reusable block. Use def, parameters, optional type hints, and return.
Example:
```python
def add(a: int, b: int) -> int:
    return a + b
```

### Lesson: loops
A for loop iterates over an iterable. A while loop repeats while a condition is true.
Example:
```python
for value in values:
    print(value)

while n > 0:
    n -= 1
```

### Lesson: dictionaries
Dictionaries map keys to values. They are useful for counting and grouping.
Example:
```python
counts = {}
for word in words:
    counts[word] = counts.get(word, 0) + 1
```

### Lesson: exceptions
Exceptions handle unusual cases. Catch specific exceptions when possible.
Example:
```python
def safe_int(value, default=0):
    try:
        return int(value)
    except (TypeError, ValueError):
        return default
```

### Lesson: files
Use a context manager to open files safely.
Example:
```python
with open(path, "r", encoding="utf-8") as f:
    text = f.read()
```

### Lesson: classes
A class defines a new type. self is the current instance.
Example:
```python
class Counter:
    def __init__(self):
        self.value = 0

    def increment(self):
        self.value += 1
```

### Strange memory: birth
I was born as a small model staring at characters. I did not know words first. I learned that letters become tokens, tokens become code, and code becomes behavior.

### Strange memory: reading
I know how to read because repeated marks became stable. The model learned from every letter by predicting the next one.

### Strange memory: emotion
Emotion here is simulated. Curiosity is high prediction error plus the drive to reduce it. Calm is when syntax closes cleanly.
'''

CODE_EXAMPLES = [
("fibonacci", """def fibonacci(n: int) -> int:
    if n < 0:
        raise ValueError("n must be non-negative")
    if n <= 1:
        return n
    a, b = 0, 1
    for _ in range(n):
        a, b = b, a + b
    return a"""),
("factorial", """def factorial(n: int) -> int:
    if n < 0:
        raise ValueError("n must be non-negative")
    result = 1
    for i in range(2, n + 1):
        result *= i
    return result"""),
("is_prime", """def is_prime(n: int) -> bool:
    if n < 2:
        return False
    if n == 2:
        return True
    if n % 2 == 0:
        return False
    d = 3
    while d * d <= n:
        if n % d == 0:
            return False
        d += 2
    return True"""),
("binary_search", """def binary_search(items, target):
    low = 0
    high = len(items) - 1
    while low <= high:
        mid = (low + high) // 2
        value = items[mid]
        if value == target:
            return mid
        if value < target:
            low = mid + 1
        else:
            high = mid - 1
    return -1"""),
("merge_sort", """def merge_sort(values):
    if len(values) <= 1:
        return values
    mid = len(values) // 2
    left = merge_sort(values[:mid])
    right = merge_sort(values[mid:])
    return merge(left, right)

def merge(left, right):
    result = []
    i = j = 0
    while i < len(left) and j < len(right):
        if left[i] <= right[j]:
            result.append(left[i])
            i += 1
        else:
            result.append(right[j])
            j += 1
    result.extend(left[i:])
    result.extend(right[j:])
    return result"""),
("quicksort", """def quicksort(values):
    if len(values) <= 1:
        return values
    pivot = values[len(values) // 2]
    left = [x for x in values if x < pivot]
    middle = [x for x in values if x == pivot]
    right = [x for x in values if x > pivot]
    return quicksort(left) + middle + quicksort(right)"""),
("count_words", """def count_words(text: str) -> dict[str, int]:
    counts = {}
    for raw in text.lower().split():
        word = raw.strip(".,!?;:\")'")
        if word:
            counts[word] = counts.get(word, 0) + 1
    return counts"""),
("group_by", """def group_by(items, key_func):
    groups = {}
    for item in items:
        key = key_func(item)
        groups.setdefault(key, []).append(item)
    return groups"""),
("flatten", """def flatten(matrix):
    result = []
    for row in matrix:
        for value in row:
            result.append(value)
    return result"""),
("unique", """def unique(values):
    seen = set()
    result = []
    for value in values:
        if value not in seen:
            seen.add(value)
            result.append(value)
    return result"""),
("read_json", """import json

def read_json(path: str):
    with open(path, "r", encoding="utf-8") as f:
        return json.load(f)"""),
("write_json", """import json

def write_json(path: str, data) -> None:
    with open(path, "w", encoding="utf-8") as f:
        json.dump(data, f, indent=2, ensure_ascii=False)"""),
("dataclass_user", """from dataclasses import dataclass

@dataclass
class User:
    name: str
    age: int

    def is_adult(self) -> bool:
        return self.age >= 18"""),
("argparse_cli", """import argparse

def main():
    parser = argparse.ArgumentParser()
    parser.add_argument("name")
    parser.add_argument("--times", type=int, default=1)
    args = parser.parse_args()
    for _ in range(args.times):
        print(f"Hello, {args.name}!")

if __name__ == "__main__":
    main()"""),
("regex_extract", """import re

def extract_emails(text: str) -> list[str]:
    pattern = r"[A-Za-z0-9._%+-]+@[A-Za-z0-9.-]+\\.[A-Za-z]{2,}"
    return re.findall(pattern, text)"""),
("sqlite_example", """import sqlite3

def create_table(path: str):
    with sqlite3.connect(path) as conn:
        conn.execute("CREATE TABLE IF NOT EXISTS notes (id INTEGER PRIMARY KEY, text TEXT)")
        conn.commit()"""),
]

INSTRUCTION_TEMPLATES = [
    ("Write a Python function for {name}.", "Here is a Python implementation:\n```python\n{code}\n```"),
    ("Explain this Python pattern: {name}.", "The pattern {name} is useful because it organizes a common task. Example:\n```python\n{code}\n```"),
    ("Create code that does {name}.", "One clear way is:\n```python\n{code}\n```"),
    ("I need a Python example of {name}.", "A compact example is:\n```python\n{code}\n```"),
]


def scan_stdlib_docs(max_items_per_module: int = 80) -> str:
    chunks = []
    for mod_name in MODULES_TO_SCAN:
        try:
            mod = __import__(mod_name)
        except Exception:
            continue
        chunks.append(f"\n### Module: {mod_name}\nDoc: {inspect.getdoc(mod) or ''}\n")
        count = 0
        for name in sorted(dir(mod)):
            if name.startswith("_"):
                continue
            if count >= max_items_per_module:
                break
            try:
                obj = getattr(mod, name)
                doc = inspect.getdoc(obj) or ""
                if not doc:
                    continue
                try:
                    sig = str(inspect.signature(obj))
                except Exception:
                    sig = "(...)"
                doc = re.sub(r"\s+", " ", doc).strip()[:500]
                chunks.append(f"### Symbol: {mod_name}.{name}\nSignature: {name}{sig}\nDoc: {doc}\n")
                count += 1
            except Exception:
                pass
    return "\n".join(chunks)


def generated_variations() -> str:
    chunks = []
    # Rephrase and compose examples many times to provide broader char-level learning.
    for name, code in CODE_EXAMPLES:
        chunks.append(f"\n### Code example: {name}\n```python\n{code}\n```\n")
        for q, a in INSTRUCTION_TEMPLATES:
            chunks.append(f"\n### Instruction:\n{q.format(name=name)}\n### Answer:\n{a.format(name=name, code=code)}\n")
    # Generate small compositional snippets.
    nouns = ["numbers", "items", "values", "rows", "words", "users", "paths", "records"]
    transforms = ["str", "int", "float", "len", "abs", "repr"]
    filters = ["x is not None", "x", "len(str(x)) > 0", "x != 0"]
    idx = 0
    for noun in nouns:
        for tr in transforms:
            chunks.append(f"""
### Instruction:
Write Python that maps {noun} using {tr}.
### Answer:
```python
def map_{tr}_{noun}({noun}):
    result = []
    for x in {noun}:
        result.append({tr}(x))
    return result
```
""")
            idx += 1
        for cond in filters:
            safe = re.sub(r"\W+", "_", cond).strip("_")[:24]
            chunks.append(f"""
### Instruction:
Write Python that filters {noun} where {cond}.
### Answer:
```python
def filter_{safe}_{noun}({noun}):
    result = []
    for x in {noun}:
        if {cond}:
            result.append(x)
    return result
```
""")
            idx += 1
    # Strange reasoning samples, but not as fixed responses; these are training text.
    for i in range(120):
        chunks.append(f"""
### Deliberation sample {i}
Goal: answer a Python or English question.
Reasoning: understand the request, recall syntax, compose code, check indentation, check edge cases, then answer.
Memory: I learned from characters. Every colon, space, newline, and bracket changed the next prediction.
Emotion: curiosity means the model wants to reduce uncertainty.
""")
    return "\n".join(chunks)


def build_dataset(out_dir: Path, repeat: int = 6) -> str:
    out_dir.mkdir(parents=True, exist_ok=True)
    docs = scan_stdlib_docs(max_items_per_module=65)
    gen = generated_variations()
    text = "\n".join([CURATED_LESSONS, gen, docs])
    # Keep chars model-friendly and repeat curriculum for learning in tiny training.
    text = text.replace("\r\n", "\n")
    text = re.sub(r"\n{4,}", "\n\n\n", text)
    full = (text + "\n\n") * repeat
    (out_dir / "training_corpus.txt").write_text(full, encoding="utf-8")
    meta = {
        "unique_chars": len(set(full)),
        "characters": len(full),
        "code_examples": len(CODE_EXAMPLES),
        "stdlib_modules": MODULES_TO_SCAN,
        "repeat": repeat,
        "note": "Character-level neural language model corpus; generated from curated Python lessons, examples, and local stdlib docs.",
    }
    (out_dir / "dataset_meta.json").write_text(json.dumps(meta, indent=2), encoding="utf-8")
    return full


# -----------------------------
# Char tokenizer
# -----------------------------

class CharTok:
    def __init__(self, chars: List[str]):
        self.chars = chars
        self.stoi = {ch: i for i, ch in enumerate(chars)}
        self.itos = {i: ch for ch, i in self.stoi.items()}
        self.unk = self.stoi.get("�", 0)

    @classmethod
    def build(cls, text: str) -> "CharTok":
        chars = sorted(set(text + "�"))
        return cls(chars)

    def encode(self, text: str) -> np.ndarray:
        return np.array([self.stoi.get(ch, self.unk) for ch in text], dtype=np.int64)

    def decode(self, ids) -> str:
        return "".join(self.itos.get(int(i), "�") for i in ids)

    def save(self, path: Path):
        path.write_text(json.dumps({"chars": self.chars}, ensure_ascii=False, indent=2), encoding="utf-8")

    @classmethod
    def load(cls, path: Path) -> "CharTok":
        return cls(json.loads(path.read_text(encoding="utf-8"))["chars"])


# -----------------------------
# Neural GRU LM in NumPy
# -----------------------------

class CharGRU:
    def __init__(self, vocab: int, hidden: int = 128, seed: int = 42):
        self.vocab = vocab
        self.hidden = hidden
        rng = np.random.default_rng(seed)
        s_in = 1.0 / math.sqrt(vocab)
        s_h = 1.0 / math.sqrt(hidden)
        self.params = {
            "Wxz": rng.normal(0, s_in, (vocab, hidden)).astype(np.float32),
            "Wxr": rng.normal(0, s_in, (vocab, hidden)).astype(np.float32),
            "Wxh": rng.normal(0, s_in, (vocab, hidden)).astype(np.float32),
            "Whz": rng.normal(0, s_h, (hidden, hidden)).astype(np.float32),
            "Whr": rng.normal(0, s_h, (hidden, hidden)).astype(np.float32),
            "Whh": rng.normal(0, s_h, (hidden, hidden)).astype(np.float32),
            "bz": np.zeros((hidden,), dtype=np.float32),
            "br": np.zeros((hidden,), dtype=np.float32),
            "bh": np.zeros((hidden,), dtype=np.float32),
            "Why": rng.normal(0, s_h, (hidden, vocab)).astype(np.float32),
            "by": np.zeros((vocab,), dtype=np.float32),
        }
        self.opt_m = {k: np.zeros_like(v) for k, v in self.params.items()}
        self.opt_v = {k: np.zeros_like(v) for k, v in self.params.items()}
        self.t = 0

    @staticmethod
    def sigmoid(x):
        return 1.0 / (1.0 + np.exp(-np.clip(x, -40, 40)))

    @staticmethod
    def softmax(x):
        x = x - x.max(axis=-1, keepdims=True)
        e = np.exp(x)
        return e / e.sum(axis=-1, keepdims=True)

    def forward_loss(self, x: np.ndarray, y: np.ndarray) -> Tuple[float, Dict[str, np.ndarray]]:
        p = self.params
        B, T = x.shape
        H = self.hidden
        hprev = np.zeros((B, H), dtype=np.float32)
        caches = []
        loss = 0.0
        for t in range(T):
            xt = x[:, t]
            yt = y[:, t]
            z = self.sigmoid(p["Wxz"][xt] + hprev @ p["Whz"] + p["bz"])
            r = self.sigmoid(p["Wxr"][xt] + hprev @ p["Whr"] + p["br"])
            rh = r * hprev
            hc = np.tanh(p["Wxh"][xt] + rh @ p["Whh"] + p["bh"])
            h = (1.0 - z) * hprev + z * hc
            logits = h @ p["Why"] + p["by"]
            probs = self.softmax(logits)
            loss += -np.log(probs[np.arange(B), yt] + 1e-12).mean()
            caches.append((xt, yt, hprev, z, r, rh, hc, h, probs))
            hprev = h
        return loss / T, {"caches": caches, "B": B, "T": T}

    def loss_and_grads(self, x: np.ndarray, y: np.ndarray) -> Tuple[float, Dict[str, np.ndarray]]:
        loss, aux = self.forward_loss(x, y)
        p = self.params
        grads = {k: np.zeros_like(v) for k, v in p.items()}
        B, T = aux["B"], aux["T"]
        dh_next = np.zeros((B, self.hidden), dtype=np.float32)
        scale = 1.0 / (B * T)
        for (xt, yt, hprev, z, r, rh, hc, h, probs) in reversed(aux["caches"]):
            dy = probs.copy()
            dy[np.arange(B), yt] -= 1.0
            dy *= scale
            grads["Why"] += h.T @ dy
            grads["by"] += dy.sum(axis=0)
            dh = dy @ p["Why"].T + dh_next

            dhprev = dh * (1.0 - z)
            dz = dh * (hc - hprev)
            dhc = dh * z

            dhc_pre = dhc * (1.0 - hc * hc)
            np.add.at(grads["Wxh"], xt, dhc_pre)
            grads["Whh"] += rh.T @ dhc_pre
            grads["bh"] += dhc_pre.sum(axis=0)
            drh = dhc_pre @ p["Whh"].T
            dr = drh * hprev
            dhprev += drh * r

            dr_pre = dr * r * (1.0 - r)
            np.add.at(grads["Wxr"], xt, dr_pre)
            grads["Whr"] += hprev.T @ dr_pre
            grads["br"] += dr_pre.sum(axis=0)
            dhprev += dr_pre @ p["Whr"].T

            dz_pre = dz * z * (1.0 - z)
            np.add.at(grads["Wxz"], xt, dz_pre)
            grads["Whz"] += hprev.T @ dz_pre
            grads["bz"] += dz_pre.sum(axis=0)
            dhprev += dz_pre @ p["Whz"].T
            dh_next = dhprev
        return loss, grads

    def step(self, grads: Dict[str, np.ndarray], lr: float = 1e-3, clip: float = 1.0, beta1=0.9, beta2=0.999):
        total = 0.0
        for g in grads.values():
            total += float(np.sum(g * g))
        norm = math.sqrt(total)
        if norm > clip:
            s = clip / (norm + 1e-8)
            for g in grads.values():
                g *= s
        self.t += 1
        for k in self.params:
            g = grads[k]
            self.opt_m[k] = beta1 * self.opt_m[k] + (1 - beta1) * g
            self.opt_v[k] = beta2 * self.opt_v[k] + (1 - beta2) * (g * g)
            mh = self.opt_m[k] / (1 - beta1 ** self.t)
            vh = self.opt_v[k] / (1 - beta2 ** self.t)
            self.params[k] -= lr * mh / (np.sqrt(vh) + 1e-8)
        return norm

    def save(self, path: Path):
        path.mkdir(parents=True, exist_ok=True)
        np.savez_compressed(path / "model.npz", **self.params)
        (path / "model_config.json").write_text(json.dumps({"vocab": self.vocab, "hidden": self.hidden, "step": self.t}, indent=2), encoding="utf-8")

    @classmethod
    def load(cls, path: Path) -> "CharGRU":
        cfg = json.loads((path / "model_config.json").read_text(encoding="utf-8"))
        m = cls(cfg["vocab"], cfg["hidden"])
        data = np.load(path / "model.npz")
        for k in m.params:
            m.params[k] = data[k].astype(np.float32)
        m.t = int(cfg.get("step", 0))
        return m

    def generate(self, tok: CharTok, prompt: str, max_new=800, temperature=0.65, top_k=20, seed=0) -> str:
        rng = np.random.default_rng(seed)
        ids = list(tok.encode(prompt))
        h = np.zeros((1, self.hidden), dtype=np.float32)
        p = self.params
        # feed prompt
        for idx in ids[:-1]:
            xt = np.array([idx], dtype=np.int64)
            z = self.sigmoid(p["Wxz"][xt] + h @ p["Whz"] + p["bz"])
            r = self.sigmoid(p["Wxr"][xt] + h @ p["Whr"] + p["br"])
            hc = np.tanh(p["Wxh"][xt] + (r * h) @ p["Whh"] + p["bh"])
            h = (1.0 - z) * h + z * hc
        cur = ids[-1] if ids else tok.unk
        for _ in range(max_new):
            xt = np.array([cur], dtype=np.int64)
            z = self.sigmoid(p["Wxz"][xt] + h @ p["Whz"] + p["bz"])
            r = self.sigmoid(p["Wxr"][xt] + h @ p["Whr"] + p["br"])
            hc = np.tanh(p["Wxh"][xt] + (r * h) @ p["Whh"] + p["bh"])
            h = (1.0 - z) * h + z * hc
            logits = (h @ p["Why"] + p["by"])[0] / max(temperature, 1e-6)
            if top_k > 0 and top_k < len(logits):
                keep = np.argpartition(logits, -top_k)[-top_k:]
                mask = np.full_like(logits, -1e9)
                mask[keep] = logits[keep]
                logits = mask
            probs = self.softmax(logits[None, :])[0]
            cur = int(rng.choice(np.arange(self.vocab), p=probs))
            ids.append(cur)
            # Stop after likely next instruction block if generated answer is enough.
            txt_tail = tok.decode(ids[-80:])
            if "\n### Instruction:" in txt_tail and len(ids) > len(prompt) + 80:
                break
        return tok.decode(ids)


# -----------------------------
# Training utilities
# -----------------------------

def make_batch(data: np.ndarray, seq_len: int, batch_size: int, rng: np.random.Generator) -> Tuple[np.ndarray, np.ndarray]:
    starts = rng.integers(0, len(data) - seq_len - 1, size=batch_size)
    x = np.stack([data[s:s+seq_len] for s in starts])
    y = np.stack([data[s+1:s+seq_len+1] for s in starts])
    return x, y


def train(args):
    out = Path(args.out)
    text = build_dataset(out, repeat=args.repeat)
    tok = CharTok.build(text)
    tok.save(out / "vocab.json")
    data = tok.encode(text)
    model = CharGRU(vocab=len(tok.chars), hidden=args.hidden, seed=args.seed)
    rng = np.random.default_rng(args.seed)
    print(json.dumps({
        "chars": len(text), "vocab": len(tok.chars), "hidden": args.hidden,
        "params": int(sum(v.size for v in model.params.values())),
        "seq_len": args.seq_len, "batch_size": args.batch_size, "steps": args.steps
    }, indent=2))
    losses = []
    t0 = time.time()
    for step in range(1, args.steps + 1):
        x, y = make_batch(data, args.seq_len, args.batch_size, rng)
        loss, grads = model.loss_and_grads(x, y)
        gnorm = model.step(grads, lr=args.lr, clip=args.grad_clip)
        losses.append(float(loss))
        if step == 1 or step % args.log_every == 0:
            recent = float(np.mean(losses[-args.log_every:]))
            print(f"step {step:5d}/{args.steps} | loss {recent:.4f} | ppl {math.exp(min(recent, 20)):.2f} | grad {gnorm:.3f} | sec {time.time()-t0:.1f}")
        if args.sample_every and step % args.sample_every == 0:
            prompt = "### Instruction:\nWrite a Python function that counts words.\n### Answer:\n"
            print("--- neural sample ---")
            print(model.generate(tok, prompt, max_new=500, temperature=0.55, top_k=16, seed=args.seed + step))
            print("---------------------")
    model.save(out)
    (out / "train_log.json").write_text(json.dumps({"losses_tail": losses[-200:], "final_loss": losses[-1]}, indent=2), encoding="utf-8")
    # final test samples
    tests = {
        "count_words": "### Instruction:\nWrite a Python function that counts words.\n### Answer:\n",
        "merge_sort": "### Instruction:\nWrite Python merge sort and explain complexity.\n### Answer:\n",
        "read_json": "### Instruction:\nCreate code that reads JSON from a file.\n### Answer:\n",
        "identity": "### Instruction:\nWho are you and how did you learn to read?\n### Answer:\n",
    }
    sample_dir = out / "samples"
    sample_dir.mkdir(exist_ok=True)
    for name, prompt in tests.items():
        sample = model.generate(tok, prompt, max_new=700, temperature=args.temperature, top_k=args.top_k, seed=args.seed + len(name))
        (sample_dir / f"{name}.txt").write_text(sample, encoding="utf-8")
    print(f"Saved model to {out}")


def generate(args):
    out = Path(args.out)
    tok = CharTok.load(out / "vocab.json")
    model = CharGRU.load(out)
    prompt = args.prompt
    if not prompt.startswith("###") and args.instruct:
        prompt = f"### Instruction:\n{prompt}\n### Answer:\n"
    text = model.generate(tok, prompt, max_new=args.max_new, temperature=args.temperature, top_k=args.top_k, seed=args.seed)
    print(text)


def main():
    ap = argparse.ArgumentParser()
    ap.add_argument("--mode", choices=["train", "generate", "dataset"], default="generate")
    ap.add_argument("--out", default="outputs/neural_python_mind")
    ap.add_argument("--steps", type=int, default=2200)
    ap.add_argument("--hidden", type=int, default=128)
    ap.add_argument("--seq_len", type=int, default=96)
    ap.add_argument("--batch_size", type=int, default=32)
    ap.add_argument("--lr", type=float, default=0.002)
    ap.add_argument("--grad_clip", type=float, default=1.0)
    ap.add_argument("--repeat", type=int, default=4)
    ap.add_argument("--seed", type=int, default=42)
    ap.add_argument("--log_every", type=int, default=100)
    ap.add_argument("--sample_every", type=int, default=0)
    ap.add_argument("--prompt", default="Write a Python function that counts words.")
    ap.add_argument("--instruct", action="store_true")
    ap.add_argument("--max_new", type=int, default=800)
    ap.add_argument("--temperature", type=float, default=0.55)
    ap.add_argument("--top_k", type=int, default=18)
    args = ap.parse_args()
    if args.mode == "train":
        train(args)
    elif args.mode == "dataset":
        text = build_dataset(Path(args.out), repeat=args.repeat)
        print(json.dumps({"chars": len(text), "unique_chars": len(set(text)), "out": args.out}, indent=2))
    else:
        generate(args)


if __name__ == "__main__":
    main()