c# httpclient azure function authorization

C#
//Append URL with code and key or add x-functions-key header.
"https://myazurecloudfunctions.azurewebsites.net/api/SayHi?code=udXhf3pviSICFMtViW/pqmV/1Q5vLH5aMcRWXfD/q6NXk2VVxRlfYw=="
Source

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