Refactor contest data import logic in app.py

- Simplified the error handling during contest data import by initializing an empty DataFrame with specified columns in case of failure.
- Moved the check for existing contest data to a more streamlined position, enhancing code readability and maintaining user feedback for duplicate uploads.

app.py

@@ -63,12 +63,11 @@ def export_contest_file(db, sport, type, contest_date, contest_id, contest_data)
     try:
         cursor = collection.find()
         contest_import = pd.DataFrame(list(cursor)).drop('_id', axis=1)
+        if contest_id in contest_import['Contest ID'].values:
+            st.info("Data for this contest already exists, no need to upload, but we appreciate the effort!")
+            return
     except:
-        contest_import = pd.DataFrame(columns = contest_data.columns)
-    
-    if contest_id in contest_import['Contest ID'].values:
-        st.info("Data for this contest already exists, no need to upload, but we appreciate the effort!")
-        return
+        contest_import = pd.DataFrame(columns = ['Rank', 'EntryId', 'EntryName', 'TimeRemaining', 'Points', 'Lineup', 'Player', 'Roster Position', '%Drafted', 'FPTS', 'Contest Date', 'Contest ID'])
     
     contest_data['Contest Date'] = contest_date
     contest_data['Contest ID'] = contest_id