Spotipy

Added
- Added unit tests for queue functions
- Added detailed function docstrings to 'util.py', including descriptions and special sections that lists arguments, returns, and raises.
- Updated order of instructions for Python and pip package manager installation in TUTORIAL.md
- Updated TUTORIAL.md instructions to match current layout of Spotify Developer Dashboard
- Added test_artist_id, test_artist_url, and test_artists_mixed_ids to non_user_endpoints test.py
- Added rate/request limit to FAQ
- Added custom `urllib3.Retry` class for printing a warning when a rate/request limit is reached.
- Added `personalized_playlist.py`, `track_recommendations.py`, and `audio_features_analysis.py` to `/examples`.
- Discord badge in README
- Added `SpotifyBaseException` and moved all exceptions to `exceptions.py`
- Marked the following methods as deprecated:
- artist_related_artists
- recommendations
- audio_features
- audio_analysis
- featured_playlists
- category_playlists
- Added FAQ entry for inaccessible playlists

Fixed
- Audiobook integration tests
- Edited docstrings for certain functions in client.py for functions that are no longer in use and have been replaced.
- `current_user_unfollow_playlist()` now supports playlist IDs, URLs, and URIs rather than previously where it only supported playlist IDs.

Removed
- `mock` no longer listed as a test dependency. Only built-in `unittest.mock` is actually used.

Added
- Added `MemcacheCacheHandler`, a cache handler that stores the token info using pymemcache.
- Added support for audiobook endpoints: `get_audiobook`, `get_audiobooks`, and `get_audiobook_chapters`.
- Added integration tests for audiobook endpoints.
- Added `update` field to `current_user_follow_playlist`.

Changed
- Fixed error obfuscation when Spotify class is being inherited and an error is raised in the Child's `__init__`
- Replaced `artist_albums(album_type=...)` with `artist_albums(include_groups=...)` due to an API change.
- Updated `_regex_spotify_url` to ignore `/intl-<countrycode>` in Spotify links
- Improved README, docs and examples

Fixed
- Readthedocs build
- Split `test_current_user_save_and_usave_tracks` unit test

Removed
- Drop support for EOL Python 3.7

Added
- Added optional `encoder_cls` argument to `CacheFileHandler`, which overwrite default encoder for token before writing to disk
- Integration tests for searching multiple types in multiple markets (non-user endpoints)
- Publish to PyPI action

Fixed
- Fixed the regex for matching playlist URIs with the format spotify:user:USERNAME:playlist:PLAYLISTID.
- `search_markets` now factors the counts of all types in the `total` rather than just the first type ([534](https://github.com/spotipy-dev/spotipy/issues/534))

Added

- Add alternative module installation instruction to README
- Added Comment to README - Getting Started for user to add URI to app in Spotify Developer Dashboard.
- Added playlist_add_tracks.py to example folder

Changed

- Modified docstring for playlist_add_items() to accept "only URIs or URLs",
with intended deprecation for IDs in v3

Fixed

- Path traversal vulnerability that may lead to type confusion in URI handling code
- Update contributing.md

Added

- Integration tests via GHA (non-user endpoints)
- Unit tests for new releases, passing limit parameter with minimum and maximum values of 1 and 50
- Unit tests for categories, omitting country code to test global releases
- Added `CODE_OF_CONDUCT.md`

Fixed

- Incorrect `category_id` input for test_category
- Assertion value for `test_categories_limit_low` and `test_categories_limit_high`
- Pin GitHub Actions Runner to Ubuntu 20 for Py27
- Fixed potential error where `found` variable in `test_artist_related_artists` is undefined if for loop never evaluates to true
- Fixed false positive test `test_new_releases` which looks up the wrong property of the JSON response object and always evaluates to true

Added

- Added `market` parameter to `album` and `albums` to address ([753](https://github.com/plamere/spotipy/issues/753)
- Added `show_featured_artists.py` to `/examples`.
- Expanded contribution and license sections of the documentation.
- Added `FlaskSessionCacheHandler`, a cache handler that stores the token info in a flask session.
- Added Python 3.10 in GitHub Actions

Fixed

- Updated the documentation to specify ISO-639-1 language codes.
- Fix `AttributeError` for `text` attribute of the `Response` object
- Require redis v3 if python2.7 (fixes readthedocs)