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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 start(name, call=None):
    '''
    Start a machine.
    @param name: Machine to start
    @type name: str
    @param call: Must be "action"
    @type call: str
    '''
    if call != 'action':
        raise SaltCloudSystemExit(
            'The instance action must be called with -a or --action.'
        )

    log.info("Starting machine: %s", name)
    vb_start_vm(name)
    machine = vb_get_machine(name)
    del machine["name"]
    return treat_machine_dict(machine)