old_contents: from .models import Event, EventActivity
  from rest_framework import serializers
  
  
  class EventSerializer(serializers.ModelSerializer):
      class Meta(object):
          model = Event
          depth = 1
  
  
  class EventSimpleSerializer(serializers.Serializer):
      pk = serializers.IntegerField()
      name = serializers.CharField(max_length=100)
      image = serializers.CharField(allow_blank=True, required=False)
      datetime = serializers.DateTimeField(required=False)
      address = serializers.CharField(allow_blank=True, required=False)
      description = serializers.CharField(allow_blank=True, required=False)
      is_registered = serializers.BooleanField()
  
  
  class EventActivitySerializer(serializers.ModelSerializer):
      class Meta(object):
          model = EventActivity
  
new_contents: from .models import Event, EventActivity
  from rest_framework import serializers
  
  
  class EventSerializer(serializers.ModelSerializer):
      class Meta(object):
          model = Event
          depth = 1
          fields = ("pk", "name", "image", "datetime", "address", "description", "is_active", "is_upcoming", "location")
  
  
  class EventSimpleSerializer(serializers.Serializer):
      pk = serializers.IntegerField()
      name = serializers.CharField(max_length=100)
      image = serializers.CharField(allow_blank=True, required=False)
      datetime = serializers.DateTimeField(required=False)
      address = serializers.CharField(allow_blank=True, required=False)
      description = serializers.CharField(allow_blank=True, required=False)
      is_registered = serializers.BooleanField()
  
  
  class EventActivitySerializer(serializers.ModelSerializer):
      class Meta(object):
          model = EventActivity
  
subject: Add explicit fields on EventSerializer