code: def _handle_substatements(self, stmt: Statement, sctx: SchemaContext) -> None:
          
          for s in stmt.substatements:
              if s.prefix:
                  key = (
                      sctx.schema_data.modules[sctx.text_mid].prefix_map[s.prefix][0]
                      + ":" + s.keyword)
              else:
                  key = s.keyword
              mname = SchemaNode._stmt_callback.get(key, "_noop")
              method = getattr(self, mname)
              method(s, sctx)
docs: Dispatch actions for substatements of `stmt`.