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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 volume_present(name, bricks, stripe=False, replica=False, device_vg=False,
                   transport='tcp', start=False, force=False, arbiter=False):
    '''
    Ensure that the volume exists

    name
        name of the volume

    bricks
        list of brick paths

    replica
        replica count for volume

    arbiter
        use every third brick as arbiter (metadata only)

        .. versionadded:: 2019.2.0

    start
        ensure that the volume is also started

    .. code-block:: yaml

        myvolume:
          glusterfs.volume_present:
            - bricks:
                - host1:/srv/gluster/drive1
                - host2:/srv/gluster/drive2

        Replicated Volume:
          glusterfs.volume_present:
            - name: volume2
            - bricks:
              - host1:/srv/gluster/drive2
              - host2:/srv/gluster/drive3
            - replica: 2
            - start: True

        Replicated Volume with arbiter brick:
          glusterfs.volume_present:
            - name: volume3
            - bricks:
              - host1:/srv/gluster/drive2
              - host2:/srv/gluster/drive3
              - host3:/srv/gluster/drive4
            - replica: 3
            - arbiter: True
            - start: True

    '''
    ret = {'name': name,
           'changes': {},
           'comment': '',
           'result': False}

    if suc.check_name(name, 'a-zA-Z0-9._-'):
        ret['comment'] = 'Invalid characters in volume name.'
        return ret

    volumes = __salt__['glusterfs.list_volumes']()
    if name not in volumes:
        if __opts__['test']:
            comment = 'Volume {0} will be created'.format(name)
            if start:
                comment += ' and started'
            ret['comment'] = comment
            ret['result'] = None
            return ret

        vol_created = __salt__['glusterfs.create_volume'](
            name, bricks, stripe,
            replica, device_vg,
            transport, start, force, arbiter)

        if not vol_created:
            ret['comment'] = 'Creation of volume {0} failed'.format(name)
            return ret
        old_volumes = volumes
        volumes = __salt__['glusterfs.list_volumes']()
        if name in volumes:
            ret['changes'] = {'new': volumes, 'old': old_volumes}
            ret['comment'] = 'Volume {0} is created'.format(name)

    else:
        ret['comment'] = 'Volume {0} already exists'.format(name)

    if start:
        if __opts__['test']:
            # volume already exists
            ret['comment'] = ret['comment'] + ' and will be started'
            ret['result'] = None
            return ret
        if int(__salt__['glusterfs.info']()[name]['status']) == 1:
            ret['result'] = True
            ret['comment'] = ret['comment'] + ' and is started'
        else:
            vol_started = __salt__['glusterfs.start_volume'](name)
            if vol_started:
                ret['result'] = True
                ret['comment'] = ret['comment'] + ' and is now started'
                if not ret['changes']:
                    ret['changes'] = {'new': 'started', 'old': 'stopped'}
            else:
                ret['comment'] = ret['comment'] + ' but failed to start. Check logs for further information'
                return ret

    if __opts__['test']:
        ret['result'] = None
    else:
        ret['result'] = True
    return ret