You can find channels according to the words you type and collect e-mail addresses for business/advertisement from them.
Imagine that you have a product in your hand and let's assume that this product is added to the meals.
You want to advertise this to someone who has a youtube channel, but you have difficulty choosing the youtube channel (contact emails or it is difficult to visit all channels)
that's exactly what YUF does.
When you write words like food hamburger ear fastfood in scan.txt and run them, it will write you the e-mails of the channels related to them.
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