Fix VersionConflict test failure

Fixes `TypeError: 'NoneType' object is not iterable` error at pkg_resources.py:632

Fixes issue #270

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branch : BB-270_fix_VersionConflict_test_failure_2
Closing (merged)

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branch : BB-270_fix_VersionConflict_test_failure_2
Merge VersionConflict test failure. Fixes #270.