Uncompress GZIP

Hello everyone,

I’m struggeling on a school project.
Actually I have a QR-Code that contains a String.
this String is a base64-encoded GZIP of a JSON file.
I need to convert this base64-encoded GZIP String to a JSON file.

Searched a while, tryed many things but nothing found.

As example here is the content of the QR-Code:

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

Can someone help me with this problem?