'Returns EBS volume object representing volume_id.
Raises exception.VolumeDoesNotExist if unsuccessful'

def get_volume(self, volume_id):

    try:
        return self.get_volumes(filters={'volume-id': volume_id})[0]
    except boto.exception.EC2ResponseError as e:
        if (e.error_code == 'InvalidVolume.NotFound'):
            raise exception.VolumeDoesNotExist(volume_id)
        raise
    except IndexError:
        raise exception.VolumeDoesNotExist(volume_id)
