def coffee_bot():
  print('welcome to the cafe!')
  
  
  
  size = get_size()
  print(size)

coffee_bot()

def get_size():
    res = input('What size drink can I get for you? \n[a] Small \n[b] Medium \n[c] Large \n> ')
    if res == 'a':
        return 'small'
    elif res == 'b':
        return 'medium'
    elif res =='c':
        return 'large'