./pants test tests/python/pants_test/backend/jvm/tasks:checkstyle_integration
Bootstrapping pants_deps with requirements:
  /Users/rjiang/workspace/pants/3rdparty/python/requirements.txt
  /Users/rjiang/workspace/pants/3rdparty/python/twitter/commons/requirements.txt
  /Users/rjiang/workspace/pants/pants-plugins/3rdparty/python/requirements.txt
Using python at /usr/bin/python2.7
Downloading <https://pypi.io/packages/source/v/virtualenv/virtualenv-15.1.0.tar.gz>...
######################################################################## 100.0%
New python executable in /Users/rjiang/workspace/pants/build-support/pants_dev_deps.venv/bin/python
Installing setuptools, pip, wheel...done.