geomet>=0.1,<0.3
six >=1.9
futures <=2.2.0
# Futures is not required for Python 3, but it works up through 2.2.0 (after which it introduced breaking syntax).
# This is left here to make sure install -r works with any runtime. When installing via setup.py, futures is omitted
# for Python 3, in favor of the standard library implementation.
# see PYTHON-393