The latest pycairo version i Portage is quite stale, being released more than a year ago. Please bump to 1.8.2.
+*pycairo-1.8.2 (24 Jan 2009) + + 24 Jan 2009; Patrick Lauer <patrick@gentoo.org> +pycairo-1.8.2.ebuild: + Bump to 1.8.2, fixes #255360