In Python, how do I split a string and keep the separators?

Here’s the simplest way to explain this. Here’s what I’m using:

re.split('\W', 'foo/bar spam\neggs')
-> ['foo', 'bar', 'spam', 'eggs']

Here’s what I want:

someMethod('\W', 'foo/bar spam\neggs')
-> ['foo', "https://stackoverflow.com/", 'bar', ' ', 'spam', '\n', 'eggs']

The reason is that I want to split a string into tokens, manipulate it, then put it back together again.