Returns a filtered version of the DynamicMap cache leaving only
        keys consistently with the newly specified values

def _filter_cache(self, dmap, kdims):
        """
        Returns a filtered version of the DynamicMap cache leaving only
        keys consistently with the newly specified values
        """
        filtered = []
        for key, value in dmap.data.items():
            if not any(kd.values and v not in kd.values for kd, v in zip(kdims, key)):
                filtered.append((key, value))
        return filtered