old_contents: from rest_framework import serializers
  
  
  class Tag(object):
      def __init__(self, name, related_tags, equivalent_names):
          self.name = name
          self.related_tags = related_tags
          self.equivalent_names = equivalent_names
  
  
  class TagSerializer(serializers.Serializer):
      name = serializers.CharField()
      related_tags = serializers.ListField(child=serializers.CharField(), allow_null=True)
      equivalent_names = serializers.ListField(child=serializers.CharField(), allow_null=True)
  
      def create(self, validated_data):
          return Tag(**validated_data)
  
  
  class Followable(object):
      def __init__(self, name, type, game, object_id, thumbnail_url="", **kwargs):
          self.name = name
          self.type = type
          self.game = game
          self.object_id = object_id
          self.thumbnail_url = thumbnail_url
          for field, value in kwargs.items():
              setattr(self, field, value)
  
  
  class FollowableSerializer(serializers.Serializer):
      name = serializers.CharField()
      type = serializers.IntegerField()
      game = serializers.IntegerField()
      object_id = serializers.IntegerField()
      default_color = serializers.CharField(allow_null=True, allow_blank=True)
      thumbnail_url = serializers.CharField(allow_blank=True, allow_null=True)
  
      def create(self, validated_data):
          return Followable(**validated_data)
  
new_contents: from rest_framework import serializers
  
  
  class Tag(object):
      def __init__(self, name, related_tags, equivalent_names):
          self.name = name
          self.related_tags = related_tags
          self.equivalent_names = equivalent_names
  
  
  class TagSerializer(serializers.Serializer):
      name = serializers.CharField()
      related_tags = serializers.ListField(child=serializers.CharField(), allow_null=True)
      equivalent_names = serializers.ListField(child=serializers.CharField(), allow_null=True)
  
      def create(self, validated_data):
          return Tag(**validated_data)
  
  
  class Followable(object):
      def __init__(self, name, type, game, object_id, thumbnail_url="", **kwargs):
          self.name = name
          self.type = type
          self.game = game
          self.object_id = object_id
          self.thumbnail_url = thumbnail_url
          for field, value in kwargs.items():
              setattr(self, field, value)
  
  
  class FollowableSerializer(serializers.Serializer):
      name = serializers.CharField()
      type = serializers.IntegerField()
      game = serializers.IntegerField()
      object_id = serializers.IntegerField()
      default_color = serializers.CharField(allow_null=True, allow_blank=True, required=False)
      thumbnail_url = serializers.CharField(allow_blank=True, allow_null=True)
  
      def create(self, validated_data):
          return Followable(**validated_data)
  
subject: Make default color not required