Replace map calls with list comprehensions

janine/janine.py

@@ -285,7 +285,7 @@ help - Gebe diese Hilfe aus'''
             await self._fetch_warnings()
 
             # Flush the warnings to disk
-            ids = list(map(lambda x: x.id, self._warnings0))
+            ids = [x.id for x in self._warnings0]
             with open(self._warnings_file, 'w') as warnings_file:
                 warnings_file.write(json.dumps(ids))
 
@@ -307,7 +307,7 @@ help - Gebe diese Hilfe aus'''
                 continue 
 
         # Find new warnings and send the new ones
-        ids = map(lambda x: x.id, self._warnings1)
+        ids = [x.id for x in self._warnings1]
         for warning in self._warnings0:
             if warning.id in ids:
                 continue