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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 _get_kwarg(self, name, kwargs):
 """ Helper to get value of a named attribute irrespective of whether it is passed with or without "@" prefix. """

        at_name = '@{}'.format(name)

        if name in kwargs:
            if at_name in kwargs:
                raise ValueError('Both {!r} and {!r} specified in kwargs'.format(name, at_name))
            return kwargs[name]

        if at_name in kwargs:
            return kwargs[at_name]

        return not_set