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No youtube playlist videos to be found - maybe API key not set ? This is the feed - https://www.googleapis.com/youtube/v3/playlistItems?part=snippet&playlistId=PLAPpl6B_7Wq8kgz1vgLPZy1IttXBDg1A0&key=AIzaSyBXsSRfvjEr5QiCzGb-8QW32Iveui1xcNs&maxResults=50
The request is not properly authorized to retrieve the specified playlist.