Disallowing multiline-lambdas was an intentional choice by the creators to prevent overly-functional code. For the same reasons that map/filter/reduce aren't in

Disallowing multiline-lambdas was an intentional choice by the creators to prevent overly-functional code. For the same reasons that map/filter/reduce aren't in the global namespace anymore. Python prefers different tools (comprehensions) to accomplish most of the same goals.