How to avoid string based on prefix using regular expression - regex

Question

I am using regular expression to identify names from a student file. Names contain prefix such as 'MR' or 'MRS' or there is no prefix only name, for an example 'MR GEORGE 51' or 'MRS GEORGE 52' or 'GEORGE 53'.
I want to extract 53 only from 'GEORGE 53' out of these three(the last one), meaning no 'MR GEORGE 51' or 'MRS GEORGE 52' should come. Note: numbers can be change, its an age.
I do know about regular expression and i tried patterns like '[^M][^R]' '[^M][^R][^S]' to identify and extract age, only when no 'MR' or 'MRS' should come as a prefix in a string. I understand through python program i can achieve this by some condition but i do want to know is there any regular expression available to do the same.

Answer 1

The [^M][^R] pattern matches any char but M followed with any char but R. Thus, you may actually reject valid matches if they are SR or ME, for example.
You may use
re.findall(r'\b(?<!\bmr\s)(?<!\bmrs\s)\S+\s+\d{1,2}\b', text, re.I)
See the regex demo. To grab the name and age into separate tuple items capture them:
re.findall(r'\b(?<!\bmr\s)(?<!\bmrs\s)(\S+)\s+(\d{1,2})\b', text, re.I)
Details
\b - word boundary
(?<!\bmr\s) - no mr + space right before the current location
(?<!\bmrs\s) - no mrs + space right before the current location
(\S+) - Group 1: one or more non-whitespace chars
\s+ - 1+ whitespaces
(\d{1,2}) - Group 2: one or two digits
\b - word boundary
The re.I is the case insensitive modifier.
Python demo:
import re
text="for an example 'MR GEORGE 51' or 'MRS GEORGE 52' or 'GEORGE 53'"
print(re.findall(r'\b(?<!\bmr\s)(?<!\bmrs\s)\S+\s+\d{1,2}\b', text, re.I))
# => ['GEORGE 53']
print(re.findall(r'\b(?<!\bmr\s)(?<!\bmrs\s)(\S+)\s+(\d{1,2})\b', text, re.I))
# => [('GEORGE', '53')]