def interm_fluent_ordering(self) -> List[str]:
        '''The list of intermediate-fluent names in canonical order.

        Returns:
            List[str]: A list of fluent names.
        '''
        interm_fluents = self.intermediate_fluents.values()
        key = lambda pvar: (pvar.level, pvar.name)
        return [str(pvar) for pvar in sorted(interm_fluents, key=key)]
The list of intermediate-fluent names in canonical order.

        Returns:
            List[str]: A list of fluent names.