How to add spaces between sentences but ignore links?

I need to put a space between sentences like:

"This is one.This is two"

should be:

"This is one. This is two"

In Python, I used the following regular expression:

text = re.sub(r'\.([A-Z])', r'. \1', text)

It worked pretty well until I have links in the text with dots inside, like:

"This is a text with link https://www.website.com/Article.Name.pdf" 

turned out to be:

"This is a text with link https://www.website.com/Article. Name.pd"

The case is important, it can't be changed. That is I need the regex to recognize it's a link and ignore it. Not sure how it can be done.