def _add_lists(list1, list2):
 if (len(list1) <= len(list2)):
  sol = ([(a + b) for (a, b) in zip(list1, list2)] + list2[len(list1):])
 else:
  sol = ([(a + b) for (a, b) in zip(list1, list2)] + list1[len(list2):])
 return sol

def _add_lists ( list1 , list2 ) : if ( len ( list1 ) <= len ( list2 ) ) : sol = ( [ ( a + b ) for ( a , b ) in zip ( list1 , list2 ) ] + list2 [ len ( list1 ) : ] ) else : sol = ( [ ( a + b ) for ( a , b ) in zip ( list1 , list2 ) ] + list1 [ len ( list2 ) : ] ) return sol
takes polynomial sequences of two annihilators a and b and returns the list of polynomials of sum of a and b .