'Create a snapshot.
For a full list of available parameters, please refer to the official
API reference:
https://developer.openstack.org/api-ref/compute/#create-snapshot'

def create_snapshot(self, volume_id, **kwargs):

    post_body = {'volume_id': volume_id}
    post_body.update(kwargs)
    post_body = json.dumps({'snapshot': post_body})
    (resp, body) = self.post('os-snapshots', post_body)
    body = json.loads(body)
    self.validate_response(schema.create_get_snapshot, resp, body)
    return rest_client.ResponseBody(resp, body)
