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This is the clearest, most complete explanation I’ve ever heard regarding add-on development. Low explains methods, classes, parameters, tagdata, and what ExpressionEngine is doing under the hood in a way I wish someone had explained to me years ago.
They’re really clear, and I actually feel like I’m learning how EE works, not just repeating things monkey-like.
Greg has an excellent way of introducing Python to a PHP developer. He covers classes and methods, working with the file system, even dictionaries, lists, and tuples explained in a way I can remember. If you are at all interested in Python then watch it. You won’t be disappointed.