def __repr__(self):
        return "<NamedRequirements({}{})>".format(
            self.name,
            ", filename='{}'".format(self.filename.name) if self.filename
            else "")
def _on_size_spin_button_value_changed(self, size_spin_button):
    if self._locker.is_unlocked("emit_size_spin_button_value_changed"):
      self._locker.lock("update_spin_button")