I am in the process of converting the SLS design related functions in the RC Design Functions spreadsheet to Python code. The current version can be downloaded from:
For details of the pyxll app required to conect the Python code to Excel see Python and pyxll
The functions currently available are:
py_EStress, py_EStressCap, py_PLCurve, py_TStiff:

MomCurveTSN:

py_CircE:

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