PBs with lambdas

[michaelbjames]

In a pilot, a participant used defaultdict, which takes a lambda to initialize values in a dictionary when the key isn't present.
The lambda didn't create a pleasant experience.

Suggestion:

1. instead of function <lambda> ..., perhaps print the text of the lambda function?
2. instead of function <lambda> ..., just the word lambda 1, lambda 2, where each number represents a unique function.