try:

                    obj = self.repository._repo[tree[path][1]]

                    if isinstance(obj, objects.Tree):

                        trees.append(obj)

                        tree = obj

                except KeyError:

                    break

            # Cut down the blob and all rotten trees on the way back...

            for path, tree in reversed(zip(paths, trees)):

                del tree[path]

                if tree:

                    # This tree still has elements - don't remove it or any

                    # of it's parents

                    break

        object_store.add_object(commit_tree)

        # Create commit

        commit = objects.Commit()

        commit.tree = commit_tree.id

        commit.parents = [p._commit.id for p in self.parents if p]

        commit.author = commit.committer = safe_str(author)

        commit.encoding = ENCODING

        commit.message = safe_str(message)

        # Compute date

        if date is None:

            date = time.time()

        elif isinstance(date, datetime.datetime):

            date = time.mktime(date.timetuple())

        author_time = kwargs.pop('author_time', date)

        commit.commit_time = int(date)

        commit.author_time = int(author_time)

        tz = time.timezone

        author_tz = kwargs.pop('author_timezone', tz)

        commit.commit_timezone = tz

        commit.author_timezone = author_tz

        object_store.add_object(commit)

        ref = 'refs/heads/%s' % branch

        repo.refs[ref] = commit.id

        repo.refs.set_symbolic_ref('HEAD', ref)

        # Update vcs repository object & recreate dulwich repo

        self.repository.revisions.append(commit.id)

        self.repository._repo = Repo(self.repository.path)

        tip = self.repository.get_changeset()

        self.reset()

        return tip

    def _get_missing_trees(self, path, root_tree):

        """

        Creates missing ``Tree`` objects for the given path.

        :param path: path given as a string. It may be a path to a file node

          (i.e. ``foo/bar/baz.txt``) or directory path - in that case it must

          end with slash (i.e. ``foo/bar/``).

        :param root_tree: ``dulwich.objects.Tree`` object from which we start

          traversing (should be commit's root tree)

        """

        dirpath = posixpath.split(path)[0]

        dirs = dirpath.split('/')

        if not dirs or dirs == ['']:

            return []

        def get_tree_for_dir(tree, dirname):

            for name, mode, id in tree.iteritems():

                if name == dirname:

                    obj = self.repository._repo[id]

                    if isinstance(obj, objects.Tree):

                        return obj

                    else:

                        raise RepositoryError("Cannot create directory %s "

                        "at tree %s as path is occupied and is not a "

                        "Tree" % (dirname, tree))

            return None

        trees = []

        parent = root_tree

        for dirname in dirs:

            tree = get_tree_for_dir(parent, dirname)

            if tree is None:

                tree = objects.Tree()

                dirmode = 040000

                parent.add(dirmode, dirname, tree.id)

                parent = tree

            # Always append tree

            trees.append(tree)

        return trees

    @LazyProperty

    def contact(self):

        undefined_contact = u'Unknown'

        return undefined_contact

    @property

    def branches(self):

        if not self.revisions:

            return {}

        sortkey = lambda ctx: ctx[0]

        _branches = [(x[0], x[1][0])

                     for x in self._parsed_refs.iteritems() if x[1][1] == 'H']

        return OrderedDict(sorted(_branches, key=sortkey, reverse=False))

    @LazyProperty

    def tags(self):

        return self._get_tags()

    def _get_tags(self):

        if not self.revisions:

            return {}

        sortkey = lambda ctx: ctx[0]

        _tags = [(x[0], x[1][0])

                 for x in self._parsed_refs.iteritems() if x[1][1] == 'T']

        return OrderedDict(sorted(_tags, key=sortkey, reverse=True))

    def tag(self, name, user, revision=None, message=None, date=None,

            **kwargs):

        """

        Creates and returns a tag for the given ``revision``.

        :param name: name for new tag

        :param user: full username, i.e.: "Joe Doe <joe.doe@example.com>"

        :param revision: changeset id for which new tag would be created

        :param message: message of the tag's commit

        :param date: date of tag's commit

        :raises TagAlreadyExistError: if tag with same name already exists

        """

        if name in self.tags:

            raise TagAlreadyExistError("Tag %s already exists" % name)

        changeset = self.get_changeset(revision)

        message = message or "Added tag %s for commit %s" % (name,

            changeset.raw_id)

        self._repo.refs["refs/tags/%s" % name] = changeset._commit.id

        self.tags = self._get_tags()

        return changeset

    def remove_tag(self, name, user, message=None, date=None):

        """

        Removes tag with the given ``name``.

        :param name: name of the tag to be removed

        :param user: full username, i.e.: "Joe Doe <joe.doe@example.com>"

        :param message: message of the tag's removal commit

        :param date: date of tag's removal commit

        :raises TagDoesNotExistError: if tag with given name does not exists

        """

        if name not in self.tags:

            raise TagDoesNotExistError("Tag %s does not exist" % name)

        tagpath = posixpath.join(self._repo.refs.path, 'refs', 'tags', name)

        try:

            os.remove(tagpath)

            self.tags = self._get_tags()

        except OSError, e:

            raise RepositoryError(e.strerror)

    @LazyProperty

    def _parsed_refs(self):

        refs = self._repo.get_refs()

        keys = [('refs/heads/', 'H'),

                ('refs/remotes/origin/', 'RH'),

                ('refs/tags/', 'T')]

        _refs = {}

        for ref, sha in refs.iteritems():

            for k, type_ in keys:

                if ref.startswith(k):

                    _key = ref[len(k):]

                    _refs[_key] = [sha, type_]

                    break

        return _refs

    def _heads(self, reverse=False):

        refs = self._repo.get_refs()

        heads = {}

        for key, val in refs.items():

            for ref_key in ['refs/heads/', 'refs/remotes/origin/']:

                if key.startswith(ref_key):

                    n = key[len(ref_key):]

                    if n not in ['HEAD']:

                        heads[n] = val

        return heads if reverse else dict((y, x) for x, y in heads.iteritems())

    def get_changeset(self, revision=None):

        """

        Returns ``GitChangeset`` object representing commit from git repository

        at the given revision or head (most recent commit) if None given.

        """

        if isinstance(revision, GitChangeset):

            return revision

        revision = self._get_revision(revision)

        changeset = GitChangeset(repository=self, revision=revision)

        return changeset

    def get_changesets(self, start=None, end=None, start_date=None,

           end_date=None, branch_name=None, reverse=False):

        """

        Returns iterator of ``GitChangeset`` objects from start to end (both

        are inclusive), in ascending date order (unless ``reverse`` is set).

        :param start: changeset ID, as str; first returned changeset

        :param end: changeset ID, as str; last returned changeset

        :param start_date: if specified, changesets with commit date less than

          ``start_date`` would be filtered out from returned set

        :param end_date: if specified, changesets with commit date greater than