JWT token claims in Django Rest Framework

I am using rest_framework_simplejwt, and would like to add extra information to the access token returned for authorization purposes. Following along with https://django-rest-framework-simplejwt.readthedocs.io/en/latest/customizing_token_claims.html I am able to modify the access token. However I want to be able to add a claim based on the initial POSTed login. For example:

curl -X POST -H 'Content-type: application/json' -d '{"username": "user1", "password": "supersecretpassword", "project": "project1"}' https://myurl.com/api/token/

I would like to be able to add project1 to the access token. Is there a way to add extra information in that manner?

Added project field to TokenObtainSerializer.

CustomTokenObtainPairSerializer has added the process of adding project values to the token payload in TokenObtainPairSerializer.

serializers.py

from django.contrib.auth.models import update_last_login
from rest_framework_simplejwt.tokens import RefreshToken
from rest_framework_simplejwt.settings import api_settings
from rest_framework_simplejwt.serializers import TokenObtainSerializer
from rest_framework import serializers


class CustomTokenObtainSerializer(TokenObtainSerializer):
  
  def __init__(self, *args, **kwargs) -> None:
    super().__init__(*args, **kwargs)
    self.fields["project"] = serializers.CharField()
    
class CustomTokenObtainPairSerializer(CustomTokenObtainSerializer):
  token_class = RefreshToken

  def validate(self, attrs):
      data = super().validate(attrs)
      refresh = self.get_token(self.user)
      refresh["project"] = attrs["project"]

      data["refresh"] = str(refresh)
      data["access"] = str(refresh.access_token)

      if api_settings.UPDATE_LAST_LOGIN:
          update_last_login(None, self.user)
      return data

To make the above Serializer class available in TokenOptainPairView, I modified the setting values related to settings.py SIMPLE_JWT.

settings.py

SIMPLE_JWT = {
  ...
  "TOKEN_OBTAIN_SERIALIZER": "yourapp.serializers.CustomTokenObtainPairSerializer",
  ...
}