assert not ""

> a=""
>>> assert a
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
AssertionError
>>> assert not a
>>> b=True
>>> assert not b
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
AssertionError
>>> assert b
>>>

e "help", "copyright", "credits" or "license" for more information.
>>> a=""
>>> assert a
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
AssertionError
>>> assert not a
>>> b=True
>>> assert not b
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
AssertionError
>>> assert b
>>>

>>> assert ""
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
AssertionError
>>> assert not ""
>>>