Why does using multiplication operator on list create list of pointers? [duplicate]

>>> rows = [['']*5]*5>>> rows[['', '', '', '', ''], ['', '', '', '', ''], ['', '', '', '', ''], ['', '', '', '', ''], ['', '', '', '', '']]>>> rows[0][0] = 'x'

Naturally, I expect rows to become:

[['x', '', '', '', ''], ['', '', '', '', ''], ['', '', '', '', ''], ['', '', '', '', ''], ['', '', '', '', '']]

Instead, I get:

[['x', '', '', '', ''], ['x', '', '', '', ''], ['x', '', '', '', ''], ['x', '', '', '', ''], ['x', '', '', '', '']]

It seems that elements of rows list are pointers to the same old ['']*5 list. Why does it work this way and is this a Python feature?