一 函数(function)

1. 文档字符串docstring

2. 可变参数args,*kwargs

3. 匿名函数lambda

4. 高阶函数map, filter, sorted

#!/usr/bin/env python
# -*- coding=utf-8 -*-
import sys
def func1(*args, **kwargs):
    """
    this function accepts any arguments
    args: positional arguments
    kwargs: key-word arguments
    """
    print 'args:', args
    print 'kwargs:', kwargs
if __name__ == "__main__":
    help(func1)
    print '=' * 15
    func1(1, 2, c=3, d=4)
    print '=' * 15
    func1(*[1, 2, 3], **{'c': 4, 'd': 5})
    print '=' * 15
    func1(*sys.argv[1:])

#!/usr/bin/env python
# -*- coding=utf-8 -*-
# lambada
print '> lambda test'
print (lambda x: x * x)(5)
print (lambda x, y: x + y)(3, 4)
li = [1, 2, 3, 4, 5]
# map
print '> map test'
print [str(i) for i in li]
print map(str, li)
print [i*i for i in li]
print map(lambda x: x*x, li)
# filter
print '> filter test'
print [i for i in li if i % 2]
print filter(lambda x: x % 2, li)
# sorted
li = ['10', '2', '9', '11']
print '> sorted test'
print sorted(li)
print sorted(li, reverse=True)
print sorted(li, key=int)
li = ['A', 'b', 'C', 'd']
print sorted(li)
print sorted(li, key=str.upper)
print sorted(li, key=lambda x: x.upper())
# other: enumerate zip
for i, n in enumerate(range(5)):
    print i, n
l1 = [1, 2, 3]
l2 = ['a', 'b', 'c']
for a, b in zip(l1, l2):
    print a, b
d = {a: b for a, b in zip(l1, l2)}
print d
dd = dict(zip(l1, l2))
print dd

二 生成器(generator)

#!/usr/bin/env python
# -*- coding=utf-8 -*-
# 列表推导式
a = [i for i in range(3)]
print type(a), a
# 字典推导式
d = {x: x*x for x in range(3)}
print type(d), d
# 元组推导式？
t = (i for i in range(3))
print type(t), t
# ============= 生成器 =================
# next
g = (i for i in range(3))
print next(t)  # 0
print next(t)  # 1
print next(t)  # 2
# print next(t)  # StopIteration
# for
g = (i for i in range(3))
for each in g:
    print each
# list
g = (i for i in range(3))
l1 = list(g)              # 一次性的
print 'l1:', l1
l2 = list(g)
print 'l2:', l2
# yield
def fib(N):
    a, b = 0, 1
    while b <= N:
        yield b
        a, b = b, a + b
f = fib(10)
print type(f), f
for each in f:
    print each

三 类(class)

#!/usr/bin/env python
# -*- coding=utf-8 -*-
# Basic
class Test(object):
    """
    docstring for class Test ...
    """
    def __init__(self, name='zoro', age=18):
        self.name = name
        self.age = age
        print self.__dict__
    def say_hello(self):
        """
        docstring for function hello ...
        """
        print 'hello {name}, you are {age} years old.'.format(**self.__dict__)
help(Test)
a = Test()
help(a.say_hello)
a.say_hello()
# 继承
class Test2(Test):
    """
    docstring for Test2 ...
    """
    def __init__(self, like, *args, **kwargs):
        super(Test2, self).__init__(*args, **kwargs)
        self.like = like
        print self.__dict__
    def show_like(self):
        print self.__dict__
        print 'I am {name}, and I like {like}'.format(**self.__dict__)
# help(Test2)
b = Test2(name='luffy', like='meat')
b.say_hello()
b.show_like()
# 类属性， 魔法方法
class A(object):
    member = []
    def __init__(self, name='zoro'):
        self.name = name
        self.member.append(name)
    def __str__(self):
        return 'There are {} members: {}'.format(len(self.member), self.member)
    __repr__ = __str__
a = A()
print a
b = A('sanji')
print b
# 装饰器
from datetime import datetime
import dateutil.parser
class A(object):
    def __init__(self, name='zoro', age=18):
        self.name = name
        self.age = age
    @property
    def info(self):
        return 'You are {name}, and you are {age} years old'.format(**self.__dict__)
    @staticmethod
    def show_time(time_str, time_fmt='%Y-%m-%d %H:%M:%S'):
        print dateutil.parser.parse(time_str).strftime(time_fmt)
a = A()
print a.info
A.show_time('20180718')