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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_qs(self):
 """ Returns a mapping that will be used to generate the query string for the api url. Any values in the the `limit_choices_to` specified on the foreign key field and any arguments specified on self.extra_query_kwargs are converted to a format that can be used in a query string and returned as a dictionary. """

        qs = url_params_from_lookup_dict(self.rel.limit_choices_to)
        if not qs:
            qs = {}

        if self.extra_query_kwargs:
            qs.update(self.extra_query_kwargs)
        return qs