Regex to match digits of specific length

Question

I am looking to match a 15 digit number (as part of a larger regex string). Right now, I have

\\d\\d\\d\\d\\d\\d\\d\\d\\d\\d\\d\\d\\d\\d\\d

Answer 1

There, are two ways i have, to limit numbers.

using len,

num = 1234
len(str(num)) <= 4

This output will be True / False.

using regular expression,

import re
num = 12324
re.match(r'(?:(?

The output will be regular expression object or None.