docs: def merge_base_attrs(attrs):
          """
          :param dict attrs: If one of the attrs is named "base\_", assume that attribute is an instance of SimpleModel mapped on a Postgresql composite type, and that the base\_ instance is of a superclass of this class. Expand the attributes of the base\_ type and assign to class attributes.
  
          psycopg2's type casting uses namedtuple() and that forbids a
          name to start with underscore, so we end it with _ instead
          """
          base = attrs.pop('base_', None)
          if base:
              d_out("SimpleModel.merge_base_attrs: base.table={0}".format(base.table))
              for name in base.table:
                  attrs[name] = base.__dict__[name]