          Creates a default instance of a basic non-relational field.
          """
          kwargs = {}
  
          if model_field.null or model_field.blank or has_default:
              kwargs['required'] = False
  
 
</s> remove         kwargs['blank'] = model_field.blank

        if model_field.null or model_field.blank:
 </s> add         if model_field.null or model_field.blank or has_default: </s> remove         if model_field.has_default():
            kwargs['required'] = False
 </s> add         if has_default: </s> remove     target = serializers.SlugRelatedField(slug_field='name', null=True)
 </s> add     target = serializers.SlugRelatedField(slug_field='name', required=False) </s> remove             title = serializers.CharField(blank=True)
 </s> add             title = serializers.CharField(required=False)
        has_default = model_field.has_default()
          Creates a default instance of a basic non-relational field.
          """
          kwargs = {}
        has_default = model_field.has_default()
  
          if model_field.null or model_field.blank or has_default:
              kwargs['required'] = False
  
keep keep add keep keep keep keep
 Use new style of `required=<bool>` not `blank` or `null` 
rest_framework/serializers.py