update in serializers in django rest instance code example

Example 1: User serializer in django rest framework

from rest_framework import serializers

class PostSerializer(serializers.ModelSerializer):
    user = serializers.PrimaryKeyRelatedField(read_only=True, default=serializers.CurrentUserDefault())
    class Meta:
        model = Post

Example 2: drf serializer

serializer = CommentSerializer(data={'email': 'foobar', 'content': 'baz'})
serializer.is_valid()
# False
serializer.errors
# {'email': ['Enter a valid e-mail address.'], 'created': ['This field is required.']}