What are the best Python documentation generators?

Pydoctor was created to improve more from Epydoc. So it is even more better that Epydoc. For the purposes of the Twisted project as epydoc has difficulties with zope.interface. Puts a fair bit of effort into resolving imports and computing inheritance hierarchies and, as it aims at documenting Twisted, knows about zope.interface's declaration API and can present information about which classes implement which interface, and vice versa.