def test var None def inner var var or test return var return inner te

>>> def test(var=None):
...     def inner():
...         var = var or 'test'
...         return var
...     return inner
... 
>>> test()()
---------------------------------------------------------------------------
UnboundLocalError                         Traceback (most recent call last)

/Users/piranha/<ipython console> in <module>()

/Users/piranha/<ipython console> in inner()

UnboundLocalError: local variable 'var' referenced before assignment