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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:

def readmodule(module, path=None):
    '''Backwards compatible interface.

    Call readmodule_ex() and then only keep Class objects from the
    resulting dictionary.'''

    res = {}
    for key, value in _readmodule(module, path or []).items():
        if isinstance(value, Class):
            res[key] = value
    return res