面向对象编程

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没有在实例化对象中，调用并修改属性时，类属性改变，对象相应的属性也会改变。

但在对象中，调用并修改了类属性，则申请了新的空间，修改类的属性不会改变对象的属性。

应该是这样。

def calc_prod(list_):

    def calc():

        j = 1

        for i in list_:

            j = j * i

        print(j)

        return j

    return calc

f = calc_prod([1,2,3])

f()

def f(x):

    return x.title()   #把每个单词的第一个字母转化为大写，其余小写

for item in map(f,['alice', 'BOB', 'CanDY']):

    print item

网络爬虫是典型的应用程序，它的工作原理就是通过不断的请求互联网的页面，并从回应中解析获取出有用的数据；数据积累后，可以有很多用处。

eval()函数可以把字符串转换为等值的结果，比如eval('1+1')，得到结果为2。

通过input()函数，输入的是字符串，需要转换为数据类型

Python 字典(Dictionary) items() 函数以列表返回可遍历的(键, 值) 元组数组。

tinydict = {'Google': 'www.google.com', 'Runoob': 'www.runoob.com', 'taobao': 'www.taobao.com'} 
print "字典值 : %s" %  tinydict.items()
 # 遍历字典列表
for key,values in  tinydict.items():    
    print key,values

输出结果：

字典值 : [('Google', 'www.google.com'), ('taobao', 'www.taobao.com'), ('Runoob', 'www.runoob.com')]

Google www.google.com
taobao www.taobao.com

Runoob www.runoob.com

一个*代表的是传入一个元组(tuple),而两个*代表的是传入一个字典(dict)

在Python的世界中，object是父子关系的顶端，所有的数据类型的父类都是它；type是类型实例关系的顶端，所有对象都是它的实例的。它们两个的关系可以这样描述：

object是一个type，object is and instance of type。即Object是type的一个实例。

# super().__init__(). ——————继承
# 在Python2中，super()的完整用法是super(自己类名，self)
# 在Python2中需要写完整，而Python3中可以简写为super()

private:私有的属性，是以双下划线'__'开头的属性。eg1:__localtion

protected:受保护的

public:公共的

def odde(x):
   return x%2==1
print(list(filter(odde,[1, 4, 6, 7, 9, 12, 17])))  #把迭代转换list类型