How to get cluster secret for docker

Hi, Im pretty new to docker. I wanted to use docker as a local cluster in graphcool. It needs clustersecret for local cluster which im not sure as where and how to obtain.

  1. I installed docker by following https://docs.docker.com/install/linux/docker-ce/ubuntu/#install-docker-ce-1
  2. Then as given in https://www.graph.cool/docs/reference/deployment/overview-ohs4asd0pe#deploying-to-a-local-cluster I gave the below commands,
    graphcool local pull
    graphcool local up
  3. Once I gave this, I got below message
    Running local Graphcool cluster localhost:60000
    Running local Faas runtime at localhost:60050
  4. But if you see in the graphcool link which gave in step2, they have given an example which contains clusterSecret.

How and where to fetch this clusterSecret? And do I have to do anything additionally to make the docker running? It would be really helpful if you could help me out with this.

docker info:
containers: 3
running: 0
stopped: 3

Thanks