Returns: The list of values for <key> if <key> is in the dictionary,
        else <default>. If <default> is not provided, an empty list is
        returned.

def getlist(self, key, default=[]):
        """
        Returns: The list of values for <key> if <key> is in the dictionary,
        else <default>. If <default> is not provided, an empty list is
        returned.
        """
        if key in self:
            return [node.value for node in self._map[key]]
        return default