@property<EOL><INDENT>def tree(self):<DEDENT>
bs = self.model.branchScale<EOL>for node in self._tree.find_clades():<EOL><INDENT>if node != self._tree.root:<EOL><INDENT>node.branch_length = self.t[self.name_to_nodeindex[node]] * bs<EOL><DEDENT><DEDENT>return self._tree<EOL>
Tree with branch lengths in codon substitutions per site.

        The tree is a `Bio.Phylo.BaseTree.Tree` object.

        This is the current tree after whatever optimizations have
        been performed so far.