今更ながら思う，あほか，と(Python)

>>> x = [1,2,3,4,5]
>>> y = [3,2,1,5,4]

>>> x*y
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: can't multiply sequence by non-int of type 'list'

>>> x+y
[1, 2, 3, 4, 5, 3, 2, 1, 5, 4]

>>> x-y
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: unsupported operand type(s) for -: 'list' and 'list'

なんの意味があるのやら