# Frequently Asked Questions

The most common questions and issues users face are aggregated to this FAQ.

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## Does Black have an API?

Not yet. _Black_ is fundamentally a command line tool. Many
[integrations](integrations/index.rst) are provided, but a Python interface is not one
of them. A simple API is being [planned](https://github.com/psf/black/issues/779)
though.

## Is Black safe to use?

Yes, for the most part. _Black_ is strictly about formatting, nothing else. But because
_Black_ is still in [beta](index.rst), some edges are still a bit rough. To combat
issues, the equivalence of code after formatting is
[checked](the_black_code_style/current_style.md#ast-before-and-after-formatting) with
limited special cases where the code is allowed to differ. If issues are found, an error
is raised and the file is left untouched.

## How stable is Black's style?

Quite stable. _Black_ aims to enforce one style and one style only, with some room for
pragmatism. However, _Black_ is still in beta so style changes are both planned and
still proposed on the issue tracker. See
[The Black Code Style](the_black_code_style/index.rst) for more details.

## Why is my file not formatted?

Most likely because it is ignored in `.gitignore` or excluded with configuration. See
[file collection and discovery](usage_and_configuration/file_collection_and_discovery.md)
for details.

## Why are Flake8's E203 and W503 violated?

Because they go against PEP 8. E203 falsely triggers on list
[slices](the_black_code_style/current_style.md#slices), and adhering to W503 hinders
readability because operators are misaligned. Disable W503 and enable the
disabled-by-default counterpart W504. E203 should be disabled while changes are still
[discussed](https://github.com/PyCQA/pycodestyle/issues/373).

## Does Black support Python 2?

For formatting, yes! [Install](getting_started.md#installation) with the `python2` extra
to format Python 2 files too! There are no current plans to drop support, but most
likely it is bound to happen. Sometime. Eventually. In terms of running _Black_ though,
Python 3.6 or newer is required.