Sounds like your happiness
Now you can find the man at: http://rfidiot.org/ , who created the script library specifically for your needs
"devices, such as the Omnikey CardMan are also supported. I am curently testing with a CardMan 5321"
You can find his Github account with details: https://github.com/AdamLaurie/RFIDIOt
It contains all the scripts that you need to start from your device with python, and it seems he has been working on this project since 2006, but I have not looked at its code.
Give us and update if it launched you!
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