                  self.error_messages['invalid'],
                  code='invalid',
                  params={'value': value},
              )
          if isinstance(converted, six.text_type):
              return JSONString(converted)
          else:
              return converted
  
      def bound_data(self, data, initial):
 
</s> remove                         if hasattr(value, '__iter__') and not isinstance(value, six.text_type):
 </s> add                         if hasattr(value, '__iter__') and not isinstance(value, str): </s> remove         if isinstance(value, six.text_type):
            return six.memoryview(b64decode(force_bytes(value)))
 </s> add         if isinstance(value, str):
            return memoryview(b64decode(force_bytes(value))) </s> remove     if issubclass(type(s), six.text_type):
 </s> add     if issubclass(type(s), str): </s> remove         if isinstance(self.permission_required, six.string_types):
 </s> add         if isinstance(self.permission_required, str): </s> remove         if not isinstance(index, (slice,) + six.integer_types):
 </s> add         if not isinstance(index, (int, slice)):
        if isinstance(converted, str):
                  self.error_messages['invalid'],
                  code='invalid',
                  params={'value': value},
              )
        if isinstance(converted, str):
              return JSONString(converted)
          else:
              return converted
  
      def bound_data(self, data, initial):
keep keep keep keep replace keep keep keep keep keep
 Refs #23919 -- Removed six.<various>_types usage

Thanks Tim Graham and Simon Charette for the reviews. 
django/contrib/postgres/forms/jsonb.py