How many passes did Michael Irvin and Alvin Harper catch in all during the season?
return Michael Irvin ;return Alvin Harper ;return catches of #1 ;return catches of #2 ;return #3 in  the  season ;return #4 in  the  season ;return number of  #5 ;return number of  #6 ;return sum of #7 and  #8
['select', 'select', 'project', 'project', 'filter', 'filter', 'aggregate', 'aggregate', 'arithmetic']