code: def start(**kwargs):
      
      if CORE_MANAGER.started:
          raise RuntimeConfigError('Current context has to be stopped to start '
                                   'a new context.')
  
      try:
          waiter = kwargs.pop('waiter')
      except KeyError:
          waiter = hub.Event()
      common_config = CommonConf(**kwargs)
      hub.spawn(CORE_MANAGER.start, *[], **{'common_conf': common_config,
                                            'waiter': waiter})
      return True
docs: Starts new context using provided configuration.
  
      Raises RuntimeConfigError if a context is already active.