How many more members di the party have in 1947 compared to 1929?
return party ;return members of #1 ;return #2 in  1947 ;return #2 in  1929 ;return the  number of  #3 ;return the  number of  #4 ;return the  difference of #5 and  #6
['select', 'project', 'filter', 'filter', 'aggregate', 'aggregate', 'arithmetic']