user
Explain the following
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assistant
: from typing import Any as A, TypeVar as T, cast as C
b: F = lambda f: lambda a: (lambda r: r(r))(lambda s: lambda x: f(lambda y: s(s)(y))(x))(a)
f: F = b(lambda r: lambda n: 1 if n < 2 else n * r(n - 1))
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Wait no. That's not it. Let me try again:
Y = lambda f: (lambda x: f(lambda a: x(x)(a)))(lambda x: f(lambda a: x(x)(a)))
fact = Y(lambda r: lambda n: 1 if n < 2 else n * r(n-1))