Comment by greener_grass

In JavaScript you can do this:

    const f = (x, y) => {
      const z = x + y;
      const w = z * 2;
      return z - w + x;
    };

In Python, you cannot do this:

    f = (
      lambda x, y:
        z = x + y;
        w = z * 2;
        return z - w + x;
    )

Instead, you need to pull it out into a def:

    def f(x, y):
      z = x + y;
      w = z * 2;
      return z - w + x;

Sometimes, this is no big deal. But other times, it's damn annoying; the language forces you to lay out your code in a less intuitive way for no obvious benefit.