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+JSF implementation: https://github.com/yurikhan/jsf/blob/master/jsf.py
+JCS implementation: https://github.com/cyberphone/json-canonicalization
+Metalink: https://www.rfc-editor.org/rfc/rfc5854.html
+Hetalink/HTTP: https://datatracker.ietf.org/doc/html/rfc6249