code: def _generate_class_comment(self, data_type):
          
          if is_struct_type(data_type):
              class_type = 'struct'
          elif is_union_type(data_type):
              class_type = 'union'
          else:
              raise TypeError('Can\'t handle type %r' % type(data_type))
  
          self.emit(comment_prefix)
          self.emit_wrapped_text(
              'The `{}` {}.'.format(fmt_class(data_type.name), class_type),
              prefix=comment_prefix)
  
          if data_type.doc:
              self.emit(comment_prefix)
              self.emit_wrapped_text(
                  self.process_doc(data_type.doc, self._docf),
                  prefix=comment_prefix)
  
          self.emit(comment_prefix)
          protocol_str = (
              'This class implements the `DBSerializable` protocol '
              '(serialize and deserialize instance methods), which is required '
              'for all Obj-C SDK API route objects.')
          self.emit_wrapped_text(
              protocol_str.format(fmt_class_prefix(data_type), class_type),
              prefix=comment_prefix)
          self.emit(comment_prefix)
docs: Emits a generic class comment for a union or struct.