See https://bitbucket.org/durin42/hg-git/issues/189/hg-pull-over-https-fails-with-mercurial-39 for a patch.
- Bug#842503: mercurial-git: Type error when cloning ht... Christophe Troestler
- Bug#842503: mercurial-git: Type error when cloni... Christophe Troestler