Refactor contest file handling in app.py for improved session state management

- Adjusted the logic for deleting 'Contest' from session state to ensure it only occurs when necessary, enhancing clarity and maintainability.
- Updated the condition for executing name matching functions to check for the presence of 'Contest_file' and 'projections_df', improving data integrity and user experience.

app.py

@@ -69,8 +69,8 @@ with tab1:
             contest_name_var = st.selectbox("Select Contest to load", contest_names)
         elif parse_type == 'Manual':
             st.session_state['Contest_file'] = st.file_uploader("Upload Contest File (CSV or Excel)", type=['csv', 'xlsx', 'xls'])
-        if 'Contest' in st.session_state:
-            del st.session_state['Contest']
+            if 'Contest' in st.session_state:
+                del st.session_state['Contest']
         if parse_type == 'Manual':
             if 'Contest_file' not in st.session_state and 'Adj_Contest' not in st.session_state:
                 st.session_state['Contest'], st.session_state['ownership_df'], st.session_state['actual_df'], st.session_state['entry_list'] = load_contest_file(st.session_state['Contest_file'], sport_select)
@@ -119,7 +119,7 @@ with tab1:
                 st.success('Projections file loaded successfully!')
                 st.dataframe(st.session_state['projections_df'].head(10))
         
-    if is_valid_input(Contest_file) and is_valid_input(projections_file):
+    if 'Contest_file' in st.session_state and 'projections_df' in st.session_state:
         st.subheader("Name Matching functions")
         if 'Adj_Contest' not in st.session_state:
             try: