while True:
    character = input ('Teken: ')

    match character:
        case 'a':
            print ('aap')

        case 'n':
            print ('noot')

        case 'm':
            print ('mies')

        case 'w' | 'z' | 'j':
            print ('wim of zus of jet')

        case 's':
            print ('Programma gestopt')
            break

        case _:
            if character.isalpha ():
                print ('Ongeldige letter')
            elif character.isdigit ():
                print ('Ongeldig cijfer')
            else:
                print ('Ongeldig symbool')