Dear Chenhui,
Check out the raise_pins() method.
https://nazca-design.org/manual/code.html?highlight=raise_pins#nazca.Instance.raise_pins
In your example ‘padN1’ is an instance of cell ‘bump’ in parent cell ‘C’. The raise_pins raises the pins of padN1 to the parent level.
padN1.raise_pins()
Ronald
