          'invalid': _('This value does not match the required pattern.')
      }
  
      def __init__(self, regex, **kwargs):
          super(RegexField, self).__init__(**kwargs)
          validator = RegexValidator(regex, message=self.error_messages['invalid'])
          self.validators.append(validator)
  
  
  class SlugField(CharField):
 
</s> remove         super(EmailField, self).__init__(**kwargs)
 </s> add         super().__init__(**kwargs) </s> remove         super(PrimaryKeyRelatedField, self).__init__(**kwargs)
 </s> add         super().__init__(**kwargs) </s> remove         super(DurationField, self).__init__(**kwargs)
 </s> add         super().__init__(**kwargs) </s> remove         super(IPAddressField, self).__init__(**kwargs)
 </s> add         super().__init__(**kwargs) </s> remove @six.add_metaclass(SerializerMetaclass)
class Serializer(BaseSerializer):
 </s> add class Serializer(BaseSerializer, metaclass=SerializerMetaclass):
        super().__init__(**kwargs)
          'invalid': _('This value does not match the required pattern.')
      }
  
      def __init__(self, regex, **kwargs):
        super().__init__(**kwargs)
          validator = RegexValidator(regex, message=self.error_messages['invalid'])
          self.validators.append(validator)
  
  
  class SlugField(CharField):
keep keep keep keep replace keep keep keep keep keep
 Dropped Python 2 compatibility. (#6615)

Thanks to Jon Dufresne (@jdufresne) for review.

Co-authored-by: Asif Saif Uddin <auvipy@gmail.com>
Co-authored-by: Rizwan Mansuri <Rizwan@webbyfox.com> 
rest_framework/fields.py