https://docs.python.org/3/reference/expressions.html#comparisons says that "a op1 b op2 c ... y opN z is equivalent to a op1 b and b op2 c and ... y opN z" and this explains the "unexpected" result:

>>> 1 in [1] == True
False
>>> 1 in [1] and [1] == True
False

"in" and "not in" are also listed among the comparison operators, so I think this behavior is expected and by design.  I don't think there's anything that needs to be fixed here.