While try this example with GNS3 branch 3.0 on Ubuntu 20.04 LTS, the API call
```$ curl http://172.17.46.114:3080/v3/users/authenticate -d '{"username": "admin", "password": "admin"}' ``` fails with ```{"detail":[{"loc":["body"],"msg":"value is not a valid dict","type":"type_error.dict"}]}```.
The additional parameter appended to curl fixes this ```{"access_token":"eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiJhZG1pbiIsImV4cCI6MTYzMTI4NTc4NX0.kT1dAN4v1vHMTBJO2UaI2I7yAFhnSpBU9iqmdDuwtAQ","token_type":"bearer"} ```
Found after googling for the error above in
FastAPI 0.65.2 POST request fails with "value is not a valid dict" when using the Requests library; 0.65.1 works (with a caveat) #3373https://github.com/tiangolo/fastapi/issues/3373#issuecomment-886745123