Python核心编程（第二版）课后习题部分代码（3-4章）（持续更新）

  本人近期研究了下Python，所用的书籍主要是Python核心编程（第二版）等，在此期间，我对书后的习题（编码部分）进行了实现，由于此书课后没有答案（英文版的答案也不全，我看的是电子书，不知道买的书后有没有答案），所以，在此把我的实现分享一下，希望对初学者有帮助。由于本人水平有限，在实现的编码中肯定有不合理的地方，希望大虾指出，我及时更正，大家共同交流。
     3-12（第三章当时做的时候有些没实现，有时间补上）
 

'''
@author: Riquelqi
'''
#!/user/bin/env python
import os
ls=os.linesep

def write():
    content=[]
    #Input a filename.
    fname=raw_input("Please input a filename:%s"%ls)
    print "Please input content(Quit with 'q'):"
    lines=raw_input(">")
    while lines!="q":
        content.append(lines)
        lines=raw_input(">")
        afile=open(fname,"w")
    afile.writelines("%s%s"%(line,ls)for line in content)
    afile.close()
    print "DONE!",
def read():
    #input a filename 
    fname=raw_input('Please input a filename:%s'%ls)
    #To be sure that the file path  exists
    if not os.path.exists(fname):
        print"File doesn't exists!"
    else:
        afile=open(fname,'r')
        for line in afile.readline():
            print line,
    print '\nDONE!' 
if __name__=='__main__':
    input=raw_input("""
     |Please input your commend|
    --|-------------------------|--    
    --|  r        |   read      |--
    --|  w        |   write     |--
    --|  q        |   quit      |--
      |Please input your commend|      
    """ )
    
    while input!='q':
        if input=='r':
            read()
        elif input=='w':
            write()
    input=raw_input("""
      |Please input your commend|
    --|-------------------------|--    
    --|  r        |   read      |--
    --|  w        |   write     |--
    --|  q        |   quit      |--
      |Please input your commend|      
    """ )       

  

    4-6（第四章感觉没有什么，不过以下我的这段练习，有助于4-6题的理解，并且这段代码也说明了很多知识）
 

'''
@author: Riquelqi
'''
# To import like this is  better than import types ,because we will use the property like that types.IntType...
# It will select twice
from types import IntType,FloatType,LongType,ComplexType
 
def display_Number_Best(number):
    print number, 'is',
    if isinstance(number,(int,long,float,complex)):
        print 'a number of type:',type(number).__name__
    else:
        print 'not a number at all',
def display_Number_Worst(number):
    print number,'is'
    if type(number)==type(0):
        print 'a number of type:',type(0).__name__
    elif type(number)==type(0L):
        print 'a number of type:',type(0L).__name__
    elif type(number)==type(0.0):
        print 'a number of type:',type(0.0).__name__
    elif type(number)==type(0.0+0.0j):
        print 'a number of type:',type(0.0+0.0j).__name__
    else :
        print 'not a number at all'
def display_Number_Better(number):
    print number,'is'
    if type(number) is IntType:
        print 'a number of type: int'
    elif type(number) is FloatType:
        print 'a number of type:float'
    elif type(number) is LongType:
        print 'a number of type:Long'
    elif type(number) is ComplexType:
        print 'a number of type:Complex'
    else:
        print 'not a number at all'
def display_Number_Good(number):
    print number,'is'
    if type(number) == IntType:
        print 'a number of type: int'
    elif type(number) == FloatType:
        print 'a number of type:float'
    elif type(number) == LongType:
        print 'a number of type:Long'
    elif type(number) == ComplexType:
        print 'a number of type:Complex'
    else:
        print 'not a number at all'      
if __name__=='__main__':
    display_Number_Best(94)
    display_Number_Best(-64)
    display_Number_Best(10.3232)
    display_Number_Best(777777777777777777777777)
    display_Number_Best(10.0+10.0j)
    display_Number_Best('qq')
#    display_Number_Worst(554454)
#    display_Number_Worst(10.11)
#    display_Number_Worst(10.0+10.0j)
#    display_Number_Worst("sdfsdfsd")    
#    display_Number_Better(45654)
#    display_Number_Better(10.0)
#    display_Number_Better(10.0+10.0j)
#    display_Number_Better(8888888888888888)
#    display_Number_Better('xxx')
#    display_Number_Good(21554)
#    display_Number_Good(8888888888888888888888888)
#    display_Number_Good(10.0)
#    display_Number_Good(10.0+10.0j)
#    display_Number_Good('my')