Fix CI

black requires 3.6+ to be installed

CHANGELOG.md

@@ -22,6 +22,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
  * Slowly removing specialization uses
  * `PyString`, `PyUnicode`, and `PyBytes` no longer have a `data()` method
  (replaced by `as_bytes()`) and `PyStringData` has been removed.
+ * The pyobject_extract macro
 
 ### Changed
  * Removes the types from the root module and the prelude. They now live in `pyo3::types` instead.
@@ -44,10 +45,6 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
  * Work around a [bug](https://github.com/rust-lang/rust/issues/55380) in the rust compiler by kngwyu [#252](https://github.com/PyO3/pyo3/pull/252)
  * Fixed a segfault with subclassing pyo3 create classes and using `__class__` by kngwyu [#263](https://github.com/PyO3/pyo3/pull/263)
 
-### Removed
-
- * The pyobject_extract macro
-
 ## [0.4.1] - 2018-08-20
 
 ### Fixed

Makefile

@@ -18,6 +18,7 @@ default: test
 test:
 	cargo test $(CARGO_FLAGS)
 	pip install tox
+	tox
 	cd examples/word-count && tox
 	cd examples/rustapi_module && tox
 

examples/rustapi_module/requirements-dev.txt

@@ -1,4 +1,3 @@
 hypothesis>=3.55
 pytest>=3.5.0
 setuptools-rust>=0.10.2
-black