def cons(a, b):
      return lambda f: f(a, b)

  def car(p):
      return p(lambda a,b: a)

  def cdr(p):
      return p(lambda a,b: b)

As well as in theory you can do this in practice. It's about as elegant (hard for me to judge as I have a strong pro-lisp bias).

Aside from lack of tail safety and performance issues with writing scheme-ish code I don't see why you couldn't implement those things in Python. The main difference is that typically in a real world situation you wouldn't because there's a library or a language feature