numpy
# We need this as long as we need support both Python 2 and 3.
six

# methods
scipy
periodictable

# bridges
biopython
openbabel
# For some reason PyQuante can't be installed from PyPI.
https://sourceforge.net/projects/pyquante/files/PyQuante-1.6/PyQuante-1.6.5/PyQuante-1.6.5.tar.gz  ; python_version <= '2.7'

# For building the documentation
sphinx

# For testing
pytest>=3.6
coverage
pytest-cov
# This library is in the standard library starting from Python 3.3.
mock ; python_version < '3.3'
