Accepts a key as input. The corresponding value must be a string or the objects (True or 1) or (False or 0). We allow 0 and 1 to retain compatibility with Python 2.2.
If the string is one of True, On, Yes, or 1 it returns True.
If the string is one of False, Off, No, or 0 it returns False.
as_bool is not case sensitive.
Any other input will raise a ValueError.
>>> a = ConfigObj()
>>> a['a'] = 'fish'
>>> a.as_bool('a')
Traceback (most recent call last):
ValueError: Value "fish" is neither True nor False
>>> a['b'] = 'True'
>>> a.as_bool('b')
1
>>> a['b'] = 'off'
>>> a.as_bool('b')
0