Travis now recommends removing `sudo: false` from configuration: https://blog.travis-ci.com/2018-11-19-required-linux-infrastructure-migration.
@@ -9,7 +9,6 @@ python:
- "3.6"
- "pypy"
- "pypy3"
-sudo: false
env:
- YTDL_TEST_SET=core
- YTDL_TEST_SET=download