A wrapper around re and regex that adds additional back references
Description
Backrefs is a wrapper around Python's built-in Re and the 3rd party Regex
library. Backrefs adds various additional back references (and a couple other
features) that are known to some regular expression engines, but not to
Python's Re and/or Regex. The supported back references actually vary depending
on the regular expression engine being used as the engine may already have
support for some.
