code: def create(self):
          
          self.logger.debug('Create subscription on server...')
  
          if not self.connection.connected:
              self.state = 'connection_pending'
              return
  
          data = {
              'command': 'subscribe',
              'identifier': self._identifier_string()
          }
  
          self.connection.send(data)
          self.state = 'pending'
docs: Subscribes at the server.