How would I write a function in Python to determine if a list of filenames matches a given pattern and which files are missing from that pattern? For example:
Input ->
KUMAR.3.txt
KUMAR.4.txt
KUMAR.6.txt
KUMAR.7.txt
KUMAR.9.txt
KUMAR.10.txt
KUMAR.11.txt
KUMAR.13.txt
KUMAR.15.txt
KUMAR.16.txt
Desired Output-->
KUMAR.5.txt
KUMAR.8.txt
KUMAR.12.txt
KUMAR.14.txt
Input -->
KUMAR3.txt
KUMAR4.txt
KUMAR6.txt
KUMAR7.txt
KUMAR9.txt
KUMAR10.txt
KUMAR11.txt
KUMAR13.txt
KUMAR15.txt
KUMAR16.txt
Desired Output -->
KUMAR5.txt
KUMAR8.txt
KUMAR12.txt
KUMAR14.txt