pyupgrade is a tool to automatically upgrade syntax for newer versions
of the Python language.

The project has been Python 3 only since
35544e2fc6eed0ce4a27ec7285aac71ff0ddc473, allowing for several cleanups:

- Remove unnecessary "-*- coding: utf-8 -*-" cookie. Python 3 reads all
  source files as utf-8 by default.

- Replace IOError/EnvironmentError with OSError. Python 3 unified these
  exceptions. The old names are aliases only.

- Use the Python 3 shorter super() syntax.

- Remove "utf8" argument form encode/decode. In Python 3, this value is
  the default.

- Remove "r" from open() calls. In Python 3, this value is the default.

- Remove u prefix from Unicode strings. In Python 3, all strings are
  Unicode.

- Replace io.open() with builtin open(). In Python 3, these functions
  are functionally equivalent.

Co-authored-by: Matthäus G. Chajdas <Anteru@users.noreply.github.com>

* all: remove "u" string prefix

* util: remove unirange

Since Python 3.3, all builds are wide unicode compatible.

* unistring: remove support for narrow-unicode builds

which stopped being relevant with Python 3.3

* Fix lexing of Idris compiler pragmas.

The regex for capturing Idris compiler pragmas did not separate the leading
percent sign from the disjunction of compiler directives correctly, which caused
issues such as "import" or "namespace" keywords to be mishighlighted, due to
confusion with the "%import" and "%name" compiler pragmas.

* Add unit test for Idris compiler directive lexing

* haskell: Fix highlighting of promoted type operators

Fixes issue #527
Patch originally written by paamayim

Run the pyupgrade tool across the project to use modern language
features.

- Use set literals
- Use dict comprehension
- Remove unnecessary numeric indexes in format string
- Remove unnecessary extra parentheses