Search notes:

show-winFileExtAssociation

Display the «file associations» of a given file extension: 
show-winFileExtAssociation .py
In particular, this command shows the (or at least some?) relevant information found in the registry under

TODO

If the key HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\FileExts\.ext\OpenWithList exists, it probably should be removed.

See also

The cmd.exe commands assoc and ftype.
Powershell module: winFileExtProgId

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