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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_command_completers(self, namespace, command):
 # type: (str, str) -> CompletionInfo """ Returns the completer method associated to the given command, or None :param namespace: The command name space. :param command: The shell name of the command :return: A CompletionConfiguration object :raise KeyError: Unknown command or name space """

        # Find the method (can raise a KeyError)
        method = self._commands[namespace][command]

        # Return the completer, if any
        return getattr(method, ATTR_COMPLETERS, None)