Need to know what is client-code while connecting to a dcs inlet endpoint for AEP?

I am trying to follow https://github.com/adobe/experience-platform-streaming-connect/blob/master/DEVELOPER_GUIDE.md documentation to create a sink connector from kafka to AEP.

to create a sink connector we have to create a sink connector instance by calling rest api of kafka connect.

IN access token based approach (as documented in above mentioned link) we need to provide 

client_id 

client code 

client secret 

I could get client id and secret from the json that I could download from adobe io based project , but could not understand what client-code refers to....??

Can someone pls help with what would be client-code value?

Many thanks in advance.