Regex Not Matching Alphanumeric Strings with Specific Length Constraints in Python 3.9
I'm testing a new approach and Could someone explain I've hit a wall trying to This might be a silly question, but I'm trying to validate alphanumeric strings in Python using regex, where the string must be exactly 8 characters long, containing both letters and numbers..... I assumed the regex pattern `^(?=.*[A-Za-z])(?=.*\d)[A-Za-z\d]{8}$` would work, but it doesn't seem to match strings like 'abc12345' or '1a2b3c4d'. I'm using the `re` module in Python 3.9 and my implementation looks like this: ```python import re pattern = r'^(?=.*[A-Za-z])(?=.*\d)[A-Za-z\d]{8}$' test_strings = ['abc12345', '12345678', 'abcdefgh', 'a1b2c3d4', 'abcd1234'] for s in test_strings: if re.match(pattern, s): print(f"'{s}' matches the pattern.") else: print(f"'{s}' does NOT match the pattern.") ``` When I run this code, the output shows that 'abc12345' and 'abcd1234' do not match, which is unexpected since they both contain both letters and numbers. I've also tried simplifying the regex to `^[A-Za-z0-9]{8}$` to check if the length restriction itself is causing issues, but that matches strings without enforcing the presence of both letters and digits. I would appreciate any insights on what I'm doing wrong and how to properly implement this regex for my specific use case. Is there a better way to structure the regex for this requirement? How would you solve this? I'm working with Python in a Docker container on macOS. Am I approaching this the right way? I'm working on a desktop app that needs to handle this. I'm coming from a different tech stack and learning Python. Any feedback is welcome!