One distinction between Lisp and Python's docstrings that he didn't mention is that in Lisp, you can (and it's normal to) give docstrings to variables; you can

One distinction between Lisp and Python's docstrings that he didn't mention is that in Lisp, you can (and it's normal to) give docstrings to variables; you can then look these up later with DOCUMENTATION or however else you read docstrings: CL-USER> (documentation '*print-readably* 'variable) "If true, all objects will be printed readably. If readable printing is impossible, an error will be signalled. This overrides the value of *PRINT-ESCAPE*." CL-USER> (documentation '+ 'variable) "the value of the most recent top level READ" CL-USER> (defvar *variable* nil "a variable") *VARIABLE* CL-USER> (documentation '*variable* 'variable) "a variable"