Monitor and compare two log files in real time

[m]

I have a script I would like to write but I am not sure of where to
start / approach. Perhaps someone could help direct me in the right
direction. Any advice is appreciated.

I would like to write a python script that monitors two log files.
If a certain string, lets say string1 shows up in logfile-A, I want to
check if that same string shows up in log file-B within 8 minutes. If
it does not show up within 8 minutes, send an email ( using sendmail
or postfix).

Do you have any suggestions?