Valid JSON giving JSONDecodeError: Expecting , delimiter
You'll need a r before """, or replace all \ with \\. This is not something you should care about when read the json from somewhere else, but something in the string itself.
data = json.loads(r"""{ "entry":{ "etag":"W/\"A0UGRK47eCp7I9B9WiRrYU0.\"" } }""")
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