What are the ids of stations that are located in San Francisco and have average bike availability above 10.
return San Francisco ;return stations of #1 ;return bike availabilities of #2 ;return the  average of #3 for each #2 ;return #2 where #4 is higher than 10 ;return ids of #5
['select', 'project', 'project', 'group', 'comparative', 'project']