We get a Python package developed by a third party. The package implements a standard mathematical model, no machine learning, no randomization. The model turned out to return incorrect results when installed on a Databricks cluster. We tried different runtime versions, including 6.2, 6.6 and even 7.0. When tested on other Python stacks (Python 3.8 on Windows 10, Python 3.8 on Ubuntu 20.04 and Python 3.7 on Ubuntu 16.04 (identical to Databricks)), it works as it should. Does anyone have an explanation why a package installed on a Databricks cluster behaves differently than the same package installed on other Python stacks?