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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 call(self, default_response=None, **query_params):
 """Perform a query to the Piwik server and return the response. :param default_response: Return value in case the query fails :param query_params: Dictionary with the parameters of the query """

        query_url = self.get_query_url(**query_params)
        return self._perform_call(query_url, default_response)