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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 kill(self, signal=None):
 """ Kill or send a signal to the container. Args: signal (str or int):
 The signal to send. Defaults to ``SIGKILL`` Raises: :py:class:`docker.errors.APIError` If the server returns an error. """


        return self.client.api.kill(self.id, signal=signal)