Prompt by example to tidy typed names

Your signup form saves names exactly as typed, so the database holds jOHN smith, MARY-JANE WATSON and o'brien. Support wants them tidied for emails and badges. An assistant will write clean_name(raw) in Python.

You could describe the rules in a paragraph. There are a lot of small cases, though, and a paragraph leaves room to guess.

Write the prompt you would give the assistant.

What you know:

• the cleaned name is for display only, and the raw value stays in the database
• many people type their names with care, such as McDonald, DeShawn and Pieter van der Berg
• Python 3.12, no new dependencies

Then, in a few sentences: why do examples work better than rules here?