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David Beazley's PyCon 2019 tutorial derives the lambda calculus from the ground up in Python, using only single-argument functions. He builds booleans, numerals and more with no other language features.

Jacques Pepin demonstrates deboning a whole chicken, quickly and with complete control. It is a short, wordless-feeling technique demo that shows a skill most cooks never learn.

Dan Wahlin's hour-long beginner course on AngularJS builds a small single-page app while covering SPAs, directives, filters and data binding. It gives an initial grounding in Angular 1.