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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_token_from_query_string(self, request, refresh_token):
 """ Extract the token if present from the request args. """

        if refresh_token:
            query_string_token_name_key = "query_string_refresh_token_name"
        else:
            query_string_token_name_key = "query_string_access_token_name"
        query_string_token_name = getattr(
            self.config, query_string_token_name_key
        )
        return request.args.get(query_string_token_name(), None)