Bugfix releases issued: 1.7.4 and 1.4.19

Today we're issuing bugfix releases in the 1.7 and 1.4 release series (the latter to correct a regression in the latest security release).

Details can be found in the release notes:

The release packages and checksums are available from our downloads page, as well as from the Python Package Index. The PGP key ID used for this release is Tim Graham: 1E8ABDC773EDE252.