docs: def delete_snapshot(self, snap_name):
          """
          Delete a named snapshot
  
          Parameters
          ----------
          symbol : `str`
              The snapshot name to delete
          """
          snapshot = self._snapshots.find_one({'name': snap_name})
          if not snapshot:
              raise NoDataFoundException("Snapshot %s not found!" % snap_name)
  
          # Remove the snapshot Id as a parent of versions
          self._versions.update_many({'parent': snapshot['_id']},
                                     {'$pull': {'parent': snapshot['_id']}})
  
          self._snapshots.delete_one({'name': snap_name})