If in one of the images, the locks are seen placed on something other than a metal fence.
return locks ;return something ;return fence ;return #3 that is metal ;return #2 besides  #4 ;return #1 placed on #5 ;return if  #6 are in  one of the  images
['select', 'select', 'select', 'filter', 'discard', 'filter', 'boolean']