def connect(self): 
        try:
            self.connection = pymongo.Connection(self.host, self.port)
            self.db = self.connection[self.name]
        except AutoReconnect:
            raise DatabaseException("It's not possible connect to the database")
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")