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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_parameter(self, twig=None, **kwargs):
 """ get a parameter from those that are variables """

        kwargs['twig'] = twig
        kwargs['check_default'] = False
        kwargs['check_visible'] = False
        ps = self.vars.filter(**kwargs)
        if len(ps)==1:
            return ps.get(check_visible=False, check_default=False)
        elif len(ps) > 1:
            # TODO: is this safe?  Some constraints may have a parameter listed
            # twice, so we can do this then, but maybe should check to make sure
            # all items have the same uniqueid?  Maybe check len(ps.uniqueids)?
            return ps.to_list()[0]
        else:
            raise KeyError("no result found")