Python except 关键字Python 关键字实例如果语句引发错误，则打印 "Something went wrong"：try: x > 3except: print("Something went wrong")完整实例：# (x > 3) will raise
Python else 关键字Python 关键字实例如果 x 大于 5 则打印 "YES"，否则打印 "NO"：x = 3if x > 5: print("YES")else: print("NO")完整实例：x = 3if x > 5: print("YES")else
Python elif 关键字Python 关键字实例如果变量 i 是争执，则打印 "YES"，如果 i 是 0 则打印 "WHATEVER"，否则打印 "NO"：for i in range(-5, 5): if i > 0: print("YES") eli
Python del 关键字Python 关键字实例删除对象：class MyClass: name = "John"del myClassprint(myClass)完整实例：class MyClass: name = "Bill"del MyClassprint(MyClass)定
Python def 关键字Python 关键字实例创建并执行函数：def my_function(): print("Hello from a function")my_function()完整实例：def my_function(): print("Hello from a fu
Python continue 关键字Python 关键字实例如果变量 i 为 5，则跳过迭代，但继续进行下一个迭代：for i in range(9): if i == 5: continue print(i)完整实例：for i in range(9
Python class 关键字Python 关键字实例创建名为 "Person" 的类：class Person: name = "Bill" age = 63完整实例：class Person: name = "Bill" age = 63print(Person.name)
Python break 关键字Python 关键字实例如果 i 大于 5，则结束循环：for i in range(9): if i > 5: break print(i)完整实例：for i in range(9): if i > 5: break print
Python assert 关键字Python 关键字实例测试条件是否返回 True：x = "hello"# 如果条件返回True，则什么也不会发生：assert x == "hello"#如果条件返回 False，则会引发 AssertionE
Python as 关键字Python 关键字实例引用日历模块 c：import calendar as cprint(c.month_name[1])完整实例：import calendar as cprint(c.month_name[1])定义和用法as 关键字用
Python and 关键字Python 关键字实例如果两条语句均为 True，则返回 Return：x = (5 > 3 and 5 < 10)print(x)完整实例：x = (5 > 3 and 5 < 10)print(x)定义和用法and 关键字是逻
Python 文件 writelines() 方法Python 文件方法实例以 "a" 打开文件行附加，然后添加文本列表来附加到该文件：f = open("demofile3.txt", "a")f.writelines(["See you soon!",
Python 文件 write() 方法Python 文件方法实例以 "a" 打开文件进行追加，然后向该文件添加一些文本：f = open("demofile2.txt", "a")f.write("See you soon!")f.close()#open a
Python 文件 writable() 方法Python 文件方法实例检查文件是否可写：f = open("demofile.txt", "a")print(f.writable())完整实例：f = open("demofile.txt", "a")print(f.writa
Python 文件 truncate() 方法Python 文件方法实例以 "a" 打开文件进行追加，然后将文件截断为 20 个字节：f = open("demofile2.txt", "a")f.truncate(20)f.close()#open and re
