Documentation says that, to create a Rgb pixel from numerical values, the old from_channels is deprecated. The compiler agrees. It's supposedly been replaced by new. But "new" doesn't work, and there's no sign of it in the code near from_channels. Did that get left out?
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This is a mistake in documentation -
Rgb) doesn't define any
new method indeed, but it is not necessary, since their only field is public. Therefore, just
Rgb([r, g, b]) should work.