pycodestyle; python_version >= '3.0'
pyflakes; python_version >= '3.0'
nose2; python_version >= '3.0'
coverage; python_version >= '3.0'
pylint; python_version > '3.0'
mypy; python_version > '3.0'
pytest; python_version > '3.0'
pytype; python_version > '3.0'