python - How do I coalesce a sequence of identical characters into just one?

Question

Suppose I have this:

My---sun--is------very-big---.

I want to replace all multiple hyphens with just one hyphen.

Answer 1

import re

astr='My---sun--is------very-big---.'

print(re.sub('-+','-',astr))
# My-sun-is-very-big-.