  class UniqueValidator:
      """
      Validator that corresponds to `unique=True` on a model field.
      """
      message = _('This field must be unique.')
  
      def __init__(self, queryset):
 
</s> remove     # Validators with `requires_context` will have the field instance
    # passed to them when the field is instantiated.
    requires_context = True
 </s> add  </s> remove     requires_context = True
 </s> add  </s> remove     def __call__(self, value):
        field = self.serializer_field

        # Determine the model field name that the serializer field corresponds to.
        field_name = field.source_attrs[0] if field.source_attrs else field.field_name

 </s> add     def set_context(self, serializer_field):
        # Determine the underlying model field name. This may not be the
        # same as the serializer field name if `source=<>` is set.
        self.field_name = serializer_field.source_attrs[0]
    Should be applied to an individual field on the serializer.
  class UniqueValidator:
      """
      Validator that corresponds to `unique=True` on a model field.
    Should be applied to an individual field on the serializer.
      """
      message = _('This field must be unique.')
  
      def __init__(self, queryset):
keep keep add keep keep keep keep
 First pass at unique_for_date, unique_for_month, unique_for_year 
rest_framework/validators.py