code: async def release(data):
      
      global session
      if not feature_flags.use_protocol_api_v2():
          session.adapter.remove_instrument('left')
          session.adapter.remove_instrument('right')
      else:
          session.adapter.cache_instruments()
      session = None
      return web.json_response({"message": "calibration session released"})
docs: Release a session
  
      :param data: Information obtained from a POST request.
      The content type is application/json.
      The correct packet form should be as follows:
      {
        'token': UUID token from current session start
        'command': 'release'
      }