Head First Python(一)

一、IDLE

1.TAB完成：先嵌入一些代码，再按TAB键。IDLE会提供一些建议，帮助你完成这个语句。

2.回退代码语句：使用shell时，Alt-P，回退到IDLE之前输入的代码语句；Alt-N，移至下一个代码语句（如果有的话）。Mac下将Alt改为Ctrl。

二、套嵌列表

输出套嵌列表：

movies = ["The Holy Grail", 1975, "Terry Jones & Terry Gilliam", 91,
                ["Graham Chapman", ["Michael Palin", "John Cleese",
                        "Terry Gilliam", "Eric Idle", "Terry Jones"]]]

print(movies)

for x in movies:
    if isinstance(x,list):
        for y in x:
            if isinstance(y,list):
                for z in y:
                    print(z)
            else:
                print(y)
    else:
        print(x)
        

改进：将重复代码变成一个函数

movies = ["The Holy Grail", 1975, "Terry Jones & Terry Gilliam", 91,
                ["Graham Chapman", ["Michael Palin", "John Cleese",
                        "Terry Gilliam", "Eric Idle", "Terry Jones"]]]

def print_lol(a_list):
    for each_item in a_list:
        if isinstance(each_item, list):
            print_lol(each_item)
        else:
            print(each_item)

print_lol(movies)

三、BIF

isinstance(),len(),print()