Update setup.py, enum module is required with Python 2.7 and < 3.4.0.
@@ -126,6 +126,7 @@ if PY2_pre_279:
if PY2_or_3_pre_34:
INSTALL_REQUIREMENTS.append('typing')
+ INSTALL_REQUIREMENTS.append('enum34')
needs_pytest = {'pytest', 'test', 'ptr'}.intersection(sys.argv)
pytest_runner = ['pytest-runner'] if needs_pytest else []
