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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 stop(name, call=None):
    '''
    Stop a VM.

    .. versionadded:: 2016.3.0

    name
        The name of the VM to stop.

    CLI Example:

    .. code-block:: bash

        salt-cloud -a stop my-vm
    '''
    if call != 'action':
        raise SaltCloudSystemExit(
            'The start action must be called with -a or --action.'
        )

    log.info('Stopping node %s', name)

    return vm_action(name, kwargs={'action': 'stop'}, call=call)