How are approximate versions filtered and matched against known Exchange build numbers in the Python code?

The code truncates the exact build number string by removing everything after the last '.' to obtain an approximate version pattern (e.g., "15.2.986" from "15.2.986.22"). It then loops through a list of known builds and checks if the approximate version is a prefix of the stored build number (up to the same depth). All matching entries (product name, date, full build) are printed. This approach is demonstrated in the Exchange version detection implementation.