Traceback (most recent call last):
  File "configparser.py", line 1138, in _unify_values
KeyError: 'irreducible-units'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "pynbody_test.py", line 1, in <module>
    import pynbody
  File "<frozen importlib._bootstrap>", line 971, in _find_and_load
  File "<frozen importlib._bootstrap>", line 955, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 665, in _load_unlocked
  File "/opt/local/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/PyInstaller/loader/pyimod03_importers.py", line 627, in exec_module
    exec(bytecode, module.__dict__)
  File "site-packages/pynbody/__init__.py", line 17, in <module>
  File "<frozen importlib._bootstrap>", line 971, in _find_and_load
  File "<frozen importlib._bootstrap>", line 955, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 665, in _load_unlocked
  File "/opt/local/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/PyInstaller/loader/pyimod03_importers.py", line 627, in exec_module
    exec(bytecode, module.__dict__)
  File "site-packages/pynbody/configuration.py", line 119, in <module>
  File "site-packages/pynbody/configuration.py", line 48, in _add_overrides_to_config_parser
  File "site-packages/pynbody/configuration.py", line 32, in _merge_defaults_for_problematic_keys
  File "configparser.py", line 781, in get
  File "configparser.py", line 1141, in _unify_values
configparser.NoSectionError: No section: 'irreducible-units'