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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(instance_id, call=None):
    '''
    Start an instance.

    CLI Examples:

    .. code-block:: bash

        salt-cloud -a start i-2f733r5n
    '''
    if call != 'action':
        raise SaltCloudSystemExit(
            'The stop action must be called with -a or --action.'
        )

    log.info('Starting instance %s', instance_id)

    params = {
        'action': 'StartInstances',
        'zone': _get_specified_zone(provider=get_configured_provider()),
        'instances.1': instance_id,
    }
    result = query(params)

    return result