If there is a bed with canopy netting tied at each of four corners.
return bed ;return canopy netting ;return #2 that #1 is with ;return corners of #3 ;return #4 that #3 is tied at ;return number of  #5 ;return if  #6 is equal to  four
['select', 'select', 'filter', 'project', 'filter', 'aggregate', 'boolean']