Moving from Ruby to Python, for me one of the initial frustrations was being unable to define multi-line anonymous functions, though eventually I accepted the wisdom of Python's conservative philosophy over Ruby's "Do what makes you happy".

But I'm glad that Guido et. al decided to keep lambda around. It feels like the right tradeoff with syntactic sugar, as one-line anonymous functions offer just enough utility in a limited scope. In contrast, having to formally define trivial functions feels like too much overhead and clutter.