git: add missing `repository.imanifestdict` methods to `gittreemanifest` The next logical step was to explicitly subclass `repository.imanifestdict`, but pytype flagged a few missing methods, because they're marked abstract. File "/mnt/c/Users/Matt/hg/hgext/git/manifest.py", line 238, in copy: Can't instantiate gittreemanifest with abstract methods dirs, fastdelta, set [not-instantiable] File "/mnt/c/Users/Matt/hg/hgext/git/manifest.py", line 287, in read: Can't instantiate gittreemanifest with abstract methods dirs, fastdelta, set [not-instantiable] File "/mnt/c/Users/Matt/hg/hgext/git/manifest.py", line 309, in read: Can't instantiate gittreemanifest with abstract methods dirs, fastdelta, set [not-instantiable] I'm not bothering to figure out how to implement them- add them to appease pytype, and put a TODO to fill in a proper implementation later.