Isomd5sum is a set of utilities for implanting a MD5 checksum in an ISO (or any block device), then verifying the checksum later. isomd5sum is not simply an MD5 of the entire ISO; it checksums the data inside a standard ISO9660 image and write block checksum information to an ISO9660 header, that will carry over to burning the CD.
This package contains Python modules for isomd5sum.