text: from rest_framework_simplejwt.serializers import TokenObtainPairSerializer
  
  
  class CustomTokenObtainPairSerializer(TokenObtainPairSerializer):
      def validate(self, attrs):
          data = super().validate(attrs)
          refresh = self.get_token(self.user)
          data['refresh'] = str(refresh)
          data['access'] = str(refresh.access_token)
  
          # Add extra responses here
          data['username'] = self.user.username
  
          return data
  