[gilch]

The misleading part wasn't from me. I'm trying to correct a common misconception here. Both "multiple" and "lines" are wrong.

Lambdas can't have single statements either. The body is only an expression. So why are we saying "multiple" (a word to distinguish from "single") if you meant to multiply statements? The number of statements is zero.

Does a try/except fit on one line? That's a try statement. Does a class? Technically possible, but typically no. That's a class statement. It's not just the "class" word, or the first line. The class statement includes its body. Many Python statement types can't fit on one line, and many others don't have to. So why are we saying "lines" to mean statements when these are not remotely the same thing?

The statement/expression distinction is a holdover from FORTRAN. Statements are just expressions that don't return a value. (Yes, Smalltalk and Haskell can implement control structures with expressions just fine, thank you.) Many functional languages do away with the distinction altogether and just use expressions. You only really need lambdas in Python for the functional style, and in functional style, expressions are all you need!