def _load_commands(self, extension):
        workbench = self.workbench
        commands = extension.get_children(Command)
        if extension.factory is not None:
            for item in extension.factory(workbench):
                if not isinstance(item, Command):
                    msg = "extension '%s' created non-Command of type '%s'"
                    args = (extension.qualified_id, type(item).__name__)
                    raise TypeError(msg % args)
                commands.append(item)
        return commands
Load the command objects for the given extension.
dataset/ETHPy150Open nucleic/enaml/enaml/workbench/core/core_plugin.py/CorePlugin._load_commands