def get_rgbval(self, index):
        assert (index >= 0) and (index < 256), \
               RGBMapError("Index must be in range 0-255 !")
        index = self.sarr[index].clip(0, 255)
        return (self.arr[0][index],
                self.arr[1][index],
                self.arr[2][index])
empty registry
dataset/ETHPy150Open ejeschke/ginga/ginga/RGBMap.py/RGBMapper.get_rgbval--crossover with--dataset/ETHPy150Open enthought/envisage/envisage/tests/extension_registry_test_case.py/ExtensionRegistryTestCase.test_empty_registry