If there are two carts, but only one of them has a canopy.
return carts ;return number of  #1 ;return if  #2 is equal to  two ;return canopy ;return #1 that has #4 ;return number of  #5 ;return if  #6 is equal to  one ;return if  both  #3 and #7 are true
['select', 'aggregate', 'boolean', 'select', 'filter', 'aggregate', 'boolean', 'boolean']