Prompt-toolkit

------------------

Fixes:
- Don't print exception messages twice for unhandled exceptions.
- Added cursor shape support.

Breaking changes:
- Drop Python 3.6 support.

------------------

New features:
- Improve rendering performance when there are many completions.

------------------

New features:
- Make ptipython respect more config changes.
(See: https://github.com/prompt-toolkit/ptpython/pull/110 )
- Improved performance of `DictionaryCompleter` for slow mappings.

Fixes:
- Call `super()` in `PythonInputFilter`. This will prevent potentially breakage
with an upcoming prompt_toolkit change.
(See: https://github.com/prompt-toolkit/python-prompt-toolkit/pull/1690 )
- Improved type annotations.
- Added `py.typed` to the `package_data`.

------------------

New features:
- For `DictionaryCompleter`: show parentheses after methods.

Fixes:
- Don't crash when trying to complete broken mappings in `DictionaryCompleter`.
- Don't crash when an older version of `black` is installed that is not
compatible.

------------------

Fixes:
- Fix handling of `SystemExit` (fixes "ValueError: I/O operation on closed
file").
- Allow usage of `await` in assignment expressions or for-loops.

------------------

Fixes:
- Made "black" an optional dependency.