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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 _apiv1_run(self, action, headers=None, **kwargs):
 """ Kept for backwards compatibility of this client See "self.clear_reference_language" """

        warnings.warn(
            "POEditor API v1 is deprecated. Use POEditorAPI._run method to call API v2",
            DeprecationWarning, stacklevel=2
        )

        url = "https://poeditor.com/api/"
        payload = kwargs
        payload.update({'action': action, 'api_token': self.api_token})

        return self._make_request(url, payload, headers)