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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 resume(name, call=None, session=None):
    '''
    Resume a vm from disk

    .. code-block:: bash

        salt-cloud -a resume xenvm01

    '''
    if call == 'function':
        raise SaltCloudException(
            'The show_instnce function must be called with -a or --action.'
        )
    if session is None:
        session = _get_session()
    log.info('Resuming VM %s', name)
    vm = _get_vm(name, session)
    task = session.xenapi.Async.VM.resume(vm, False, True)
    _run_async_task(task, session)
    return show_instance(name)