Send variable to json object repository

Hello. I was wondering if someone could help me figure out what I’m doing wrong. I currently have a testcase setup that looks like this:

response = WS.sendRequest(findTestObject(‘Object Repository/REST_GetToken1’, “superuser”,“superpass”))

it should go out to the post REST JSON item i created that looks like this:

{ “username”: {{userName}},

“password”: {{userPassword}} }

basically the variables i passed in i would expect to input for user name and password respectively, however I think i’m doing something wrong and can’t seem to figure out what it is. If anyone could chime in and tell me what i’m doing wrong i would appreciate it

I found some instructors on how to use the params at
Could you have a look at it? For multiple params calling, following format could be used:

[('username') : GlobalVariable.username, ('password') : password]