Another disturbing thing is that Python does hoisting like JS.

if it encounters a (implicit) declaration of a var somewhere at the end of a function, it will bind all var to the same private storage.

see demo of the mess in fun2()

>>> a=666       # global
>>> def fun1():
...    print a  # global
... 
>>> def fun2():
...    print a  # privat
...    a = 33   # declaration
... 
>>> fun1()
666
>>> fun2()
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "<stdin>", line 2, in fun2
UnboundLocalError: local variable 'a' referenced before assignment
>>>
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