替换字符串中的占位符：
name = "Alice"age = 30message = "My name is {} and I am {} years old.".format(name, age)print(message)name = "Alice"age = 30message = "My name is {1} and I am {0} years old.".format(age, name)print(message)num = 123.456789formatted_num = "{:.2f}".format(num)print(formatted_num) # 输出：123.46from datetime import datetimenow = datetime.now()formatted_date = now.strftime("%Y-%m-%d %H:%M:%S")print(formatted_date)person = {"name": "Alice", "age": 30}message = "My name is {name} and I am {age} years old.".format(**person)print(message)itEMS = ["apple", "banana", "cherry"]message = "I like {} and {} and {}.".format(*items)print(message)
