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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 _process_file_continue_response(self, response: HTTPResponse):
        '''Process a partial content response.'''
        code = response.status_code

        if code == http.client.PARTIAL_CONTENT:
            self.open_file(self._filename, response, mode='ab+')
        else:
            self._raise_cannot_continue_error()