+- `g:black_fast` (defaults to `0`)
+- `g:black_linelength` (defaults to `88`)
+- `g:black_skip_string_normalization` (defaults to `0`)
+- `g:black_virtualenv` (defaults to `~/.vim/black` or `~/.local/share/nvim/black`)
+
+To install with [vim-plug](https://github.com/junegunn/vim-plug):
+
+```
+Plug 'psf/black'
+```
+
+or with [Vundle](https://github.com/VundleVim/Vundle.vim):
+
+```
+Plugin 'psf/black'
+```
+
+or you can copy the plugin from
+[plugin/black.vim](https://github.com/psf/black/tree/master/plugin/black.vim).
+
+```
+mkdir -p ~/.vim/pack/python/start/black/plugin
+curl https://raw.githubusercontent.com/psf/black/master/plugin/black.vim -o ~/.vim/pack/python/start/black/plugin/black.vim
+```
+
+Let me know if this requires any changes to work with Vim 8's builtin `packadd`, or
+Pathogen, and so on.
+
+This plugin **requires Vim 7.0+ built with Python 3.6+ support**. It needs Python 3.6 to
+be able to run _Black_ inside the Vim process which is much faster than calling an
+external command.
+
+On first run, the plugin creates its own virtualenv using the right Python version and
+automatically installs _Black_. You can upgrade it later by calling `:BlackUpgrade` and
+restarting Vim.
+
+If you need to do anything special to make your virtualenv work and install _Black_ (for
+example you want to run a version from master), create a virtualenv manually and point
+`g:black_virtualenv` to it. The plugin will use it.
+
+To run _Black_ on save, add the following line to `.vimrc` or `init.vim`:
+
+```
+autocmd BufWritePre *.py execute ':Black'
+```
+
+To run _Black_ on a key press (e.g. F9 below), add this:
+
+```
+nnoremap <F9> :Black<CR>
+```
+
+**How to get Vim with Python 3.6?** On Ubuntu 17.10 Vim comes with Python 3.6 by
+default. On macOS with Homebrew run: `brew install vim`. When building Vim from source,
+use: `./configure --enable-python3interp=yes`. There's many guides online how to do
+this.
+
+### Visual Studio Code
+
+Use the
+[Python extension](https://marketplace.visualstudio.com/items?itemName=ms-python.python)
+([instructions](https://code.visualstudio.com/docs/python/editing#_formatting)).
+
+### SublimeText 3
+
+Use [sublack plugin](https://github.com/jgirardet/sublack).
+
+### Jupyter Notebook Magic
+
+Use [blackcellmagic](https://github.com/csurfer/blackcellmagic).
+
+### Python Language Server
+
+If your editor supports the [Language Server Protocol](https://langserver.org/) (Atom,
+Sublime Text, Visual Studio Code and many more), you can use the
+[Python Language Server](https://github.com/palantir/python-language-server) with the
+[pyls-black](https://github.com/rupert/pyls-black) plugin.
+
+### Atom/Nuclide
+
+Use [python-black](https://atom.io/packages/python-black).
+
+### Kakoune
+
+Add the following hook to your kakrc, then run black with `:format`.
+
+```
+hook global WinSetOption filetype=python %{
+ set-option window formatcmd 'black -q -'
+}
+```
+
+### Thonny
+
+Use [Thonny-black-code-format](https://github.com/Franccisco/thonny-black-code-format).
+
+### Other editors
+
+Other editors will require external contributions.
+
+Patches welcome! ✨ 🍰 ✨
+
+Any tool that can pipe code through _Black_ using its stdio mode (just
+[use `-` as the file name](https://www.tldp.org/LDP/abs/html/special-chars.html#DASHREF2)).
+The formatted code will be returned on stdout (unless `--check` was passed). _Black_
+will still emit messages on stderr but that shouldn't affect your use case.
+
+This can be used for example with PyCharm's or IntelliJ's
+[File Watchers](https://www.jetbrains.com/help/pycharm/file-watchers.html).
+
+## blackd
+
+`blackd` is a small HTTP server that exposes _Black_'s functionality over a simple
+protocol. The main benefit of using it is to avoid paying the cost of starting up a new
+_Black_ process every time you want to blacken a file.
+
+### Usage
+
+`blackd` is not packaged alongside _Black_ by default because it has additional
+dependencies. You will need to do `pip install black[d]` to install it.
+
+You can start the server on the default port, binding only to the local interface by
+running `blackd`. You will see a single line mentioning the server's version, and the
+host and port it's listening on. `blackd` will then print an access log similar to most
+web servers on standard output, merged with any exception traces caused by invalid
+formatting requests.
+
+`blackd` provides even less options than _Black_. You can see them by running
+`blackd --help`:
+
+```text
+Usage: blackd [OPTIONS]
+
+Options:
+ --bind-host TEXT Address to bind the server to.
+ --bind-port INTEGER Port to listen on
+ --version Show the version and exit.
+ -h, --help Show this message and exit.
+```
+
+There is no official blackd client tool (yet!). You can test that blackd is working
+using `curl`:
+
+```
+blackd --bind-port 9090 & # or let blackd choose a port
+curl -s -XPOST "localhost:9090" -d "print('valid')"
+```
+
+### Protocol
+
+`blackd` only accepts `POST` requests at the `/` path. The body of the request should
+contain the python source code to be formatted, encoded according to the `charset` field
+in the `Content-Type` request header. If no `charset` is specified, `blackd` assumes
+`UTF-8`.
+
+There are a few HTTP headers that control how the source is formatted. These correspond
+to command line flags for _Black_. There is one exception to this: `X-Protocol-Version`
+which if present, should have the value `1`, otherwise the request is rejected with
+`HTTP 501` (Not Implemented).
+
+The headers controlling how code is formatted are:
+
+- `X-Line-Length`: corresponds to the `--line-length` command line flag.
+- `X-Skip-String-Normalization`: corresponds to the `--skip-string-normalization`
+ command line flag. If present and its value is not the empty string, no string
+ normalization will be performed.
+- `X-Fast-Or-Safe`: if set to `fast`, `blackd` will act as _Black_ does when passed the
+ `--fast` command line flag.
+- `X-Python-Variant`: if set to `pyi`, `blackd` will act as _Black_ does when passed the
+ `--pyi` command line flag. Otherwise, its value must correspond to a Python version or
+ a set of comma-separated Python versions, optionally prefixed with `py`. For example,
+ to request code that is compatible with Python 3.5 and 3.6, set the header to
+ `py3.5,py3.6`.
+- `X-Diff`: corresponds to the `--diff` command line flag. If present, a diff of the
+ formats will be output.
+
+If any of these headers are set to invalid values, `blackd` returns a `HTTP 400` error
+response, mentioning the name of the problematic header in the message body.
+
+Apart from the above, `blackd` can produce the following response codes:
+
+- `HTTP 204`: If the input is already well-formatted. The response body is empty.
+- `HTTP 200`: If formatting was needed on the input. The response body contains the
+ blackened Python code, and the `Content-Type` header is set accordingly.
+- `HTTP 400`: If the input contains a syntax error. Details of the error are returned in
+ the response body.
+- `HTTP 500`: If there was any kind of error while trying to format the input. The
+ response body contains a textual representation of the error.
+
+The response headers include a `X-Black-Version` header containing the version of
+_Black_.
+
+## Version control integration
+
+Use [pre-commit](https://pre-commit.com/). Once you
+[have it installed](https://pre-commit.com/#install), add this to the
+`.pre-commit-config.yaml` in your repository:
+
+```yaml
+repos:
+ - repo: https://github.com/psf/black
+ rev: stable
+ hooks:
+ - id: black
+ language_version: python3.6
+```
+
+Then run `pre-commit install` and you're ready to go.
+
+Avoid using `args` in the hook. Instead, store necessary configuration in
+`pyproject.toml` so that editors and command-line usage of Black all behave consistently
+for your project. See _Black_'s own
+[pyproject.toml](https://github.com/psf/black/blob/master/pyproject.toml) for an
+example.
+
+If you're already using Python 3.7, switch the `language_version` accordingly. Finally,
+`stable` is a tag that is pinned to the latest release on PyPI. If you'd rather run on
+master, this is also an option.
+
+## Ignoring unmodified files
+
+_Black_ remembers files it has already formatted, unless the `--diff` flag is used or
+code is passed via standard input. This information is stored per-user. The exact
+location of the file depends on the _Black_ version and the system on which _Black_ is
+run. The file is non-portable. The standard location on common operating systems is:
+
+- Windows:
+ `C:\\Users\<username>\AppData\Local\black\black\Cache\<version>\cache.<line-length>.<file-mode>.pickle`
+- macOS:
+ `/Users/<username>/Library/Caches/black/<version>/cache.<line-length>.<file-mode>.pickle`
+- Linux:
+ `/home/<username>/.cache/black/<version>/cache.<line-length>.<file-mode>.pickle`
+
+`file-mode` is an int flag that determines whether the file was formatted as 3.6+ only,
+as .pyi, and whether string normalization was omitted.
+
+To override the location of these files on macOS or Linux, set the environment variable
+`XDG_CACHE_HOME` to your preferred location. For example, if you want to put the cache
+in the directory you're running _Black_ from, set `XDG_CACHE_HOME=.cache`. _Black_ will
+then write the above files to `.cache/black/<version>/`.
+
+## Used by
+
+The following notable open-source projects trust _Black_ with enforcing a consistent
+code style: pytest, tox, Pyramid, Django Channels, Hypothesis, attrs, SQLAlchemy,
+Poetry, PyPA applications (Warehouse, Pipenv, virtualenv), pandas, Pillow, every Datadog
+Agent Integration, Home Assistant.
+
+Are we missing anyone? Let us know.
+
+## Testimonials
+
+**Dusty Phillips**,
+[writer](https://smile.amazon.com/s/ref=nb_sb_noss?url=search-alias%3Daps&field-keywords=dusty+phillips):
+
+> _Black_ is opinionated so you don't have to be.
+
+**Hynek Schlawack**, [creator of `attrs`](https://www.attrs.org/), core developer of
+Twisted and CPython:
+
+> An auto-formatter that doesn't suck is all I want for Xmas!
+
+**Carl Meyer**, [Django](https://www.djangoproject.com/) core developer:
+
+> At least the name is good.
+
+**Kenneth Reitz**, creator of [`requests`](http://python-requests.org/) and
+[`pipenv`](https://docs.pipenv.org/):
+
+> This vastly improves the formatting of our code. Thanks a ton!
+
+## Show your style
+
+Use the badge in your project's README.md:
+
+```markdown
+[![Code style: black](https://img.shields.io/badge/code%20style-black-000000.svg)](https://github.com/psf/black)
+```
+
+Using the badge in README.rst:
+
+```
+.. image:: https://img.shields.io/badge/code%20style-black-000000.svg
+ :target: https://github.com/psf/black
+```
+
+Looks like this:
+[![Code style: black](https://img.shields.io/badge/code%20style-black-000000.svg)](https://github.com/psf/black)
+
+## License
+
+MIT
+
+## Contributing to _Black_
+
+In terms of inspiration, _Black_ is about as configurable as _gofmt_. This is
+deliberate.
+
+Bug reports and fixes are always welcome! However, before you suggest a new feature or
+configuration knob, ask yourself why you want it. If it enables better integration with
+some workflow, fixes an inconsistency, speeds things up, and so on - go for it! On the
+other hand, if your answer is "because I don't like a particular formatting" then you're
+not ready to embrace _Black_ yet. Such changes are unlikely to get accepted. You can
+still try but prepare to be disappointed.
+
+More details can be found in [CONTRIBUTING](CONTRIBUTING.md).
+
+## Change Log
+
+The log's become rather long. It moved to its own file.
+
+See [CHANGES](CHANGES.md).