Cannot pass UserDict to eval()?

[Frank Niessink]

Hi,

This works:

>>> eval('x+1',{},{'x':1})
2

But this doesn't:

>>> import UserDict
>>> u = UserDict.UserDict({'x':1})
>>> eval('x+1',{},u)
Traceback (innermost last):
  File "<stdin>", line 1, in ?
TypeError: eval, argument 3: expected dictionary, instance found


Why are instances not allowed?

Cheers, Frank

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