          if value is None:
              return None
          if timezone.is_aware(value):
              raise ValueError("Django does not support timezone-aware times.")
          return six.text_type(value)
  
      def adapt_decimalfield_value(self, value, max_digits=None, decimal_places=None):
          """
          Transforms a decimal.Decimal value to an object compatible with what is
          expected by the backend driver for decimal (numeric) columns.
 
</s> remove         return six.text_type(value)
 </s> add         return str(value) </s> remove         return six.text_type(value)
 </s> add         return str(value) </s> remove         return six.text_type(value)
 </s> add         return str(value) </s> remove         if isinstance(value, six.string_types):
 </s> add         if isinstance(value, str): </s> remove         return six.text_type(value)
 </s> add         return str(value)
        return str(value)
          if value is None:
              return None
          if timezone.is_aware(value):
              raise ValueError("Django does not support timezone-aware times.")
        return str(value)
  
      def adapt_decimalfield_value(self, value, max_digits=None, decimal_places=None):
          """
          Transforms a decimal.Decimal value to an object compatible with what is
          expected by the backend driver for decimal (numeric) columns.
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/db/backends/base/operations.py