If two birds are close up, while 4 or more birds are flying high in the distance.
return birds ;return #1 that are close up ;return number of  #2 ;return if  #3 is equal to  two ;return #1 that are flying high ;return #5 that are in  the  distance ;return number of  #6 ;return if  #7 is at least 4 ;return if  both  #3 and #8 are true
['select', 'filter', 'aggregate', 'boolean', 'filter', 'filter', 'aggregate', 'boolean', 'boolean']