Is_prime function via regex in python (from perl)

I've read this article where the /^1?$|^(11+?)\1+$/ Perl regex is used to test if a number is prime or not.

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s = '1' * your_number

If s matchs the regex, then it's not prime. If it doesn't, it's prime.

How would you translate that regex to Python's re module?

It works as is (except without the slashes at the edges, which aren't needed in Python):

pattern = r'^1?$|^(11+?)\1+$'
re.match(pattern, '1'*10)    #matches
re.match(pattern, '1'*11)    #doesn't match

The only nonstandard regex feature needed here is backreferences (\1), and these are supported in both Perl and Python.