Update app.py

app.py

@@ -35,8 +35,11 @@ def get_xml(url):
     # xpath is only for formula1
     # use urllib.parse to check for formula1.com website or other news
     xml = pd.read_xml(url,xpath='channel/item')
+    return xml
 
-previous_xml = pd.DataFrame()
+cols_list = ['title', 'description', 'link', 'creator', 'guid']
+
+previous_xml = pd.DataFrame(columns=cols_list)
 
 
 # care taken to only consider results where there are more words not a single word quotes
@@ -247,7 +250,7 @@ def send_tweets(speaker_quote):
 def check_updates(every=300):
     while True:
         time.sleep(every) 
-        latest_xml = get_xml()
+        latest_xml = get_xml(URL)
         if ~previous_xml.equals(latest_xml):
             print('New articles found')
             new_articles_df = latest_xml[~latest_xml["guid"].isin(previous_xml["guid"])]