Update master

Author: Travis CI dpl test (via Travis CI)

user/languages/python.md

@@ -158,8 +158,6 @@ If you're using tox to test your code against multiple versions of Python, you h
   * use `language: generic` and manually install the Python versions you're interested in before running tox (without the manual installation, tox will only have access to the default Ubuntu Python versions - 2.7.12 and 3.5.1 for Xenial)
   * use `language: python` and a build matrix that uses a different version of Python for each branch (you can specify the Python version by using the `python` key). This will ensure the versions you're interested in are installed and parallelizes your workload.
 
-A good example of a `travis.yml` that runs tox using a Travis build matrix is [twisted/klein](https://github.com/twisted/klein/blob/master/.travis.yml).
-
 ## Running Python tests on multiple Operating Systems
 
 Sometimes it is necessary to ensure that software works the same across multiple Operating Systems.  This following `.travis.yml` file will execute parallel test runs on Linux, macOS, and Windows.