docs: def map_ormclass(self, name):
          """ Populate _mapped attribute with orm class
  
          Parameters
          ----------
          name : str
              Component part of orm class name. Concatenated with _prefix.
          """
  
          try:
              self._mapped[name] = getattr(self._pkg, self._prefix + name)
  
          except AttributeError:
              print('Warning: Relation %s does not exist.' % name)