Refactor PDF export functionality in app.py

- Replaced the previous PDF conversion method with a new implementation that converts DataFrames to HTML before generating PDFs using pdfkit.
- Added error handling to notify users if pdfkit is not installed, ensuring a smoother user experience.
- This update enhances the PDF export capabilities of the application, providing better support for exporting data in PDF format.

app.py

@@ -9,7 +9,7 @@ import numpy as np
 import pandas as pd
 import streamlit as st
 import gspread
-import gc
+import pdfkit
 
 @st.cache_resource
 def init_conn():
@@ -99,7 +99,15 @@ def convert_df_to_csv(df):
     return df.to_csv().encode('utf-8')
 
 def convert_df_to_pdf(df):
-    return df.to_pdf().encode('utf-8')
+    # Convert DataFrame to HTML first
+    html = df.to_html()
+    # Convert HTML to PDF using pdfkit
+    try:
+        pdf = pdfkit.from_string(html, False)
+        return pdf
+    except ImportError:
+        st.error("pdfkit is not installed. Please install pdfkit and wkhtmltopdf to enable PDF export.")
+        return None
 
 matchups, overall_ms, team_frame, team_list, team_dict = init_baselines()