old_contents: from core.models.identity import Identity
  from rest_framework import serializers
  from .quota_serializer import QuotaSerializer
  from .allocation_serializer import AllocationSerializer
  
  
  class IdentitySerializer(serializers.ModelSerializer):
      created_by = serializers.CharField(source='creator_name')
      credentials = serializers.ReadOnlyField(source='get_credentials')
      id = serializers.ReadOnlyField(source='uuid')
      provider_id = serializers.ReadOnlyField(source='provider_uuid')
      quota = QuotaSerializer(source='get_quota')
      allocation = AllocationSerializer(source='get_allocation')
      # membership = serializers.ReadOnlyField(source='get_membership')
  
      class Meta:
          model = Identity
          fields = ('id', 'created_by', 'provider_id', 'credentials', 'quota', 'allocation')
new_contents: from core.models.identity import Identity
  from rest_framework import serializers
  from .quota_serializer import QuotaSerializer
  from .allocation_serializer import AllocationSerializer
  
  
  class IdentitySerializer(serializers.ModelSerializer):
      created_by = serializers.ReadOnlyField(source='creator_name')
      credentials = serializers.ReadOnlyField(source='get_credentials')
      id = serializers.ReadOnlyField(source='uuid')
      provider_id = serializers.ReadOnlyField(source='provider_uuid')
      quota = QuotaSerializer(source='get_quota')
      allocation = AllocationSerializer(source='get_allocation')
      # membership = serializers.ReadOnlyField(source='get_membership')
  
      class Meta:
          model = Identity
          fields = ('id', 'created_by', 'provider_id', 'credentials', 'quota', 'allocation')
subject: update created_by field to be read only