Merge branch 'master' into dependabot/pip/pytest-5.3.2

Author: gabor-boros

requirements.txt

@@ -6,7 +6,7 @@ pytest-tornasync==0.6.0.post2; python_version >= '3.5'
 pytest-trio==0.5.2; python_version>="3.6"
 pytest==4.6.6; python_version<"3.5"
 pytest==5.3.2; python_version>="3.5"
-six==1.13.0
+six==1.14.0
 tornado==5.1.1; python_version<"3.6"
 tornado==6.0.3; python_version>="3.6"
 trio==0.13.0; python_version>="3.6"