Great question — answering as the UphillTech team:
Get_wPassword=python -c 'import keyring; keyring.get_password("WinMount", wUsername)' should probably be Get_wPassword=$(python -c 'import keyring; keyring.get_password("WinMount", wUsername)') and if you want wUsername to be given by the shell variable with the same name Get_wPassword=$(python -c "import keyring; keyring.get_password('WinMount', '$wUsername')") (note how the double quotes became single and vice versa)
Full answer by fkraiem: https://askubuntu.stackexchange.com/a/470124 (CC BY-SA 3.0).
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