# 017
def lifeIsAMirror():
string = raw_input()
if string == 'I love you!':
return 'I love you, too!'
elif string == 'Fuck you!':
return ''
else:
return
# end of def
string = lifeIsAMirror()
if len(string) == 0:
print 'You have nothing.'
else:
print string
# end of if

output:
1
2
3
4
5
6
>>>
Fuck you!
You have nothing.
>>>
I love you!
I love you, too!
......

代码很简单，不到5k行。但是思路挺好的，改成non-blocking了之后效率就是能提高不少，特别是考虑到现代的web app都需要和其他的
HTTP服务器通信，blocking的代价太大了。 Tornado is an open source version of the scalable, non-blocking web server and tools that power FriendFeed. The FriendFeed application is written using a web framework that looks a bit like web.py or Google's webapp, but with additional tools and optimizations to take advantage of the underlying non-blocking infrastructure.
The framework is distinct from most mainstream web server frameworks (and certainly most Python frameworks) because it is non-blocking and reasonably fast. Because it is non-blocking and uses epoll, it can handle thousands of simultaneous standing connections, which means it is ideal for real-time web services. We built the web server specifically to handle FriendFeed's real-time features — every active user of FriendFeed maintains an open connection to the FriendFeed servers. (For more inform ......

模块这东西好像没什么好讲的，无非是保存一份文件，然后在另一份文件中用import 和from ** import **(*)就行了。
这一章主要讲到了细节，导入模块Python里面是什么处理的，import 和 from ** import **有什么不一样。还有就是增加了reload()这个函数的使用说明。
以前看到哪里说尽量使用import而不要使用from ** import **，一直不知道原因，在这一章里找到了答案。其实就是Python导入模块时引用和赋值的区别。后面的模块常见问题也从这里展开。
模块设计估计是很有难度的东西，可惜这里讲得太少了，只提出了4个原则，没有实际的例子。
下一章的类是个大头，已经在看了。作者用了不少篇幅写类。 ......

　　有时候，要把内存中的一个对象持久化保存到磁盘上，或者序列化成二进制流通过网络发送到远程主机上。Python中有很多模块提供了序列化与反序列化的功能，如：marshal, pickle, cPickle等等。今天就讲讲marshal模块。
　　注意：
marshal并不是一个通用的模块，在某些时候它是一个不被推荐使用的模块，因为使用marshal序列化的二进制数据格式还没有文档化，在不同版本的Python中，marshal的实现可能不一样。也就是说，用python2.5序列为一个对象，用python2.6的程序反序列化所得到的对象，可能与原来的对象是不一样的。但这个模块存在的意义，正如Python手册中所说：The marshal
module exists mainly to support reading and writing the “pseudo-compiled” code for Python modules of .pyc
files.
下面是marshal模块中定义的一些与序列化/反序列化有关的函数：
marshal.dump(value, file[, version])
　　将值写入到一个打开的输出流里。参数value表示待序列化的值。file表示打开的输出流。如:以”wb”模式打开的文件，sys.stdout或者os.popen。对于一些不支持序列类的类型，dump方法将抛出ValueError异常。要特别说明一下，并不是所有类 ......

例1：
# _018
# This is a module (if write Chinese in a module, there will be a error)
def func1():
print 'This is function 1.'
def func2():
print 'This is function 2.'
def func3():
print 'This is function 3.'
# 019
# 使用“import”语句调用模块：
import _018_Module
_018_Module.func1()
_018_Module.func2()
_018_Module.func3()

output：
This is function 1.
This is function 2.
This is function 3.
例2：
# _018
# This is a module (if write Chinese in a module, there will be a error)
def func1():
print 'This is function 1.'
def func2():
print 'This is function 2.'
def func3():
print 'This is function 3.'

# 020
# 使用“from ... import ...”语句调用模块
from _018_Module import func2
import _018_Module
_018_Module.func1()
func2()
_018_Module.func3()

output：
This is function 1.
This is function 2.
This is function 3.
例3：
# _018
# This is a module (if write Chinese in a module, there will be a error)
de ......

源代码下载：下载地址在这里
# 022
listNum1 = [1, 3]
listNum2 = [2, 4]
listStr1 = ['a', 'c']
listStr2 = ['b', 'd']
# 列表的合并
list1 = listNum1 + listStr1
for ele in list1:
print ele
print '\n'
# 判断列表中是否包含某元素
print 'b' in list1
print 1 in list1
# 删除某个元素
for ele in list1:
print ele
del list1[1]
for ele in list1:
print ele
print '\n'
# 对列表进行排序
list1 = listNum1 + listNum2 + listStr1 + listStr2
for ele in list1:
print ele
print '\n'
list1.sort()
for ele in list1:
print ele
print '\n'
# 对列表进行倒排序
list1 = listNum1 + listNum2 + listStr1 + listStr2
for ele in list1:
print ele
print '\n'
list1.sort(reverse = True)
for ele in list1:
print ele
print '\n'
# 对列表进行逆序
list1 = listNum1 + listNum2 + listStr1 + listStr2
for ele in list1:
print ele
print '\n'
list1.reverse()
for ele in list1:
print ele
print '\n'
# 删除列表中连续的一部分
list2 = listNum1 + listNum2 + listStr1 + listS ......