code: def update(self, version, reason=None):
          
          _check_version_format(version)
          return self.collection.update({'_id': 'manifest'}, {
              '$set': {'version': version},
              '$push': {'history': {
                  'timestamp': datetime.utcnow(), 'version': version,
                  'reason': reason}}
          })
docs: Modify the datamodel's manifest
  
          :param version: New version of the manifest
          :param reason: Optional reason of the update (i.g. "Update from x.y.z")