If there are 3 crabs stacked on top of each other, all three are upside down
return crabs ;return #1 that are stacked on top of each other ;return #2 that are upside down ;return number of  #2 ;return number of  #3 ;return if  #4 is equal to  three ;return if  #5 is equal to  three ;return if  both  #6 and #7 are true
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