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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 exec_container_commands(self, action, c_name, **kwargs):
 """ Runs all configured commands of a container configuration inside the container instance. :param action: Action configuration. :type action: dockermap.map.runner.ActionConfig :param c_name: Container name. :type c_name: unicode | str :return: List of exec command return values (e.g. containing the command id), if applicable, or ``None`` if either no commands have been run or no values have been returned from the API. :rtype: list[dict] | NoneType """

        config_cmds = action.config.exec_commands
        if not config_cmds:
            return None
        return self.exec_commands(action, c_name, run_cmds=config_cmds)