Enhancement: Improve Python Embedding to avoid requiring logic to be run upon import

[georgemccabe]

The current implementation of Python Embedding is to import the user's script and then look for the required variables, e.g. met_data, to read data and attributes. This requires the logic to populate these variables to be run when the script is imported. This has been discovered to be problematic for scripts that use multiprocessing, as that logic should be executed when the script is executed, e.g. not called upon import but called when the script is run (__name__ == '__main__'). This paradigm also restricts how the scripts can be used for other purposes. For example, one cannot include useful functions that can imported into other scripts for use outside of Python Embedding if the logic is run when it is imported.

Describe the Enhancement

Review and enhance the existing logic so that it will work if the script is run instead of just imported. We will need to ensure backwards compatibility so that existing Python Embedding scripts still work.

Time Estimate

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Issues should represent approximately 1 to 3 days of work.

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Define Related Issue(s)

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• METplus, MET, METdataio, METviewer, METexpress, METcalcpy, METplotpy

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