Change quotes in comments for consistency

IA.py

@@ -69,8 +69,8 @@ def select_final_time(conn, day, id):
 
 def parse_time_string(timestring):
     """
-    Parse given 24h time string of format 'HH:MM' into time_struct
-    :param timestring: time string 'HH:MM'
+    Parse given 24h time string of format "HH:MM" into time_struct
+    :param timestring: time string "HH:MM"
     """
     timestruct = time.strptime(timestring, "%H:%M")
     return timestruct