import re
s = """curl -X POST -H "Content-type: application/json" -d '{"group":"stash-adt_ooms-dev","users":['stack', 'overflow']}' "url" """
res = re.sub(r"\[.*?]", lambda x: x.group().replace("'", '"'), s)
print(res)
aW1wb3J0IHJlCnMgPSAiIiJjdXJsIC1YIFBPU1QgLUggIkNvbnRlbnQtdHlwZTogYXBwbGljYXRpb24vanNvbiIgLWQgJ3siZ3JvdXAiOiJzdGFzaC1hZHRfb29tcy1kZXYiLCJ1c2VycyI6WydzdGFjaycsICdvdmVyZmxvdyddfScgInVybCIgIiIiCnJlcyA9IHJlLnN1YihyIlxbLio/XSIsIGxhbWJkYSB4OiB4Lmdyb3VwKCkucmVwbGFjZSgiJyIsICciJyksIHMpCnByaW50KHJlcyk=