>>> add_integer = __import__('0-add_integer').add_integer

>>> add_integer(0, 0)
0
>>> add_integer(42, 0)
42
>>> add_integer(0, 38)
38
>>> add_integer(-7, 7)
0
>>> add_integer(13, -13)
0
>>> add_integer(10)
108
>>> add_integer()
Traceback (most recent call last):
TypeError: add_integer() missing 1 required positional argument: 'a'
>>> add_integer('a', 'b')
Traceback (most recent call last):
TypeError: a must be an integer
>>> add_integer('a', 42)
Traceback (most recent call last):
TypeError: a must be an integer
>>> add_integer('a')
Traceback (most recent call last):
TypeError: a must be an integer
>>> add_integer(42, 'b')
Traceback (most recent call last):
TypeError: b must be an integer
>>> add_integer(float('inf'), 0)
Traceback (most recent call last):
...
OverflowError: cannot convert float infinity to integer
