#!/usr/bin/env python

class H2O:
    def __init__(self):
        pass


    def hydrogen(self, releaseHydrogen: 'Callable[[], None]') -> None:
        
        # releaseHydrogen() outputs "H". Do not change or remove this line.
        releaseHydrogen()


    def oxygen(self, releaseOxygen: 'Callable[[], None]') -> None:
        
        # releaseOxygen() outputs "O". Do not change or remove this line.
        releaseOxygen()