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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 _has_argument(func):
 """Test whether a function expects an argument. :param func: The function to be tested for existence of an argument. """

    if hasattr(inspect, 'signature'):
        # New way in python 3.3
        sig = inspect.signature(func)
        return bool(sig.parameters)
    else:
        # Old way
        return bool(inspect.getargspec(func).args)