          if field.has_default():
              default = field.get_default()
          elif not field.null and field.blank and field.empty_strings_allowed:
              if field.get_internal_type() == "BinaryField":
                  default = six.binary_type()
              else:
                  default = six.text_type()
          elif getattr(field, 'auto_now', False) or getattr(field, 'auto_now_add', False):
              default = datetime.now()
              internal_type = field.get_internal_type()
 
</s> remove                 default = six.text_type()
 </s> add                 default = str() </s> remove         elif f.geom_type == 'RASTER' and isinstance(value, six.string_types):
 </s> add         elif f.geom_type == 'RASTER' and isinstance(value, str): </s> remove         elif f.geom_type == 'RASTER' and isinstance(value, six.string_types):
 </s> add         elif f.geom_type == 'RASTER' and isinstance(value, str): </s> remove         elif isinstance(model, six.string_types):
 </s> add         elif isinstance(model, str): </s> remove             if (isinstance(dim, six.string_types) and 'Z' in dim) or dim == 3:
 </s> add             if (isinstance(dim, str) and 'Z' in dim) or dim == 3:
                default = bytes()
          if field.has_default():
              default = field.get_default()
          elif not field.null and field.blank and field.empty_strings_allowed:
              if field.get_internal_type() == "BinaryField":
                default = bytes()
              else:
                  default = six.text_type()
          elif getattr(field, 'auto_now', False) or getattr(field, 'auto_now_add', False):
              default = datetime.now()
              internal_type = field.get_internal_type()
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/schema.py