Python模块练习

import sys,pprint
import math
import copy

pprint.pprint(sys.path)
print(dir(copy))#查看模块包含的内容
print([n for n in dir(copy) if not n.startswith('_') ])#过滤掉 _xxx_



#-------------------------输出结果----------------------------------#
"""
C:\python3.7\python.exe D:/Python-Test/qiubai/qiubai/Test8.py
['D:\\Python-Test\\qiubai\\qiubai',
 'D:\\Python-Test\\qiubai',
 'C:\\python3.7\\python36.zip',
 'C:\\python3.7\\DLLs',
 'C:\\python3.7\\lib',
 'C:\\python3.7',
 'C:\\python3.7\\lib\\site-packages']
['Error', '__all__', '__builtins__', '__cached__', '__doc__', '__file__', '__loader__', '__name__', '__package__', '__spec__', '_copy_dispatch', '_copy_immutable', '_deepcopy_atomic', '_deepcopy_dict', '_deepcopy_dispatch', '_deepcopy_list', '_deepcopy_method', '_deepcopy_tuple', '_keep_alive', '_reconstruct', 'copy', 'deepcopy', 'dispatch_table', 'error']
['Error', 'copy', 'deepcopy', 'dispatch_table', 'error']
"""

print(help(print()))#获取帮助
#-------------------------输出结果----------------------------------#
"""
C:\python3.7\python.exe D:/Python-Test/qiubai/qiubai/Test8.py

Help on NoneType object:

class NoneType(object)
 |  Methods defined here:
 |
 |  __bool__(self, /)
 |      self != 0
 |
 |  __new__(*args, **kwargs) from builtins.type
 |      Create and return a new object.  See help(type) for accurate signature.
 |
 |  __repr__(self, /)

"""
print(range.__doc__)#查看range有哪些参数
#-------------------------输出结果----------------------------------#
"""
C:\python3.7\python.exe D:/Python-Test/qiubai/qiubai/Test8.py
range(stop) -> range object
range(start, stop[, step]) -> range object

Return an object that produces a sequence of integers from start (inclusive)
to stop (exclusive) by step.  range(i, j) produces i, i+1, i+2, ..., j-1.
start defaults to 0, and stop is omitted!  range(4) produces 0, 1, 2, 3.
These are exactly the valid indices for a list of 4 elements.
When step is given, it specifies the increment (or decrement).
"""


print(copy.__file__)#查看copy的源码路径
#-------------------------输出结果----------------------------------#
"""
C:\python3.7\lib\copy.py
"""

#时间
import time
print(time.asctime())#将时间元组转为字符串
print(time.localtime())#将秒数转为时间元组
#-------------------------输出结果----------------------------------#
"""
Mon Aug 14 14:06:27 2017
time.struct_time(tm_year=2017, tm_mon=8, tm_mday=14, tm_hour=14, tm_min=6, tm_sec=27, tm_wday=0, tm_yday=226, tm_isdst=0)
"""


#random随机数
from random import *
from time import *
date1 = (2008,1,1,1,0,0,-1,-1,-1)
time1 = mktime(date1)
date2 = (2009,1,1,1,0,0,-1,-1,-1)
time2 = mktime(date2)
print(asctime(localtime(uniform(time1,time2))))#将数字转换为易读的日期

#-------------------------输出结果----------------------------------#
"""
C:\python3.7\python.exe D:/Python-Test/qiubai/qiubai/Test8.py
Thu Oct 23 19:22:33 2008
"""

#shelve模块  在文件中存储数据
#open函数会返回一个shelf对象，可以用它来存储内容,只需将它当做普通字典操作
import shelve
shelf = shelve.open("shelve.txt")
shelf['x']=['a','b','c']
shelf['x'].append('d')#为什d没有添加进去
print(shelf['x'])
#需将临时变量绑定到获取的副本上，并且在它修改后重新存储这个副本
tmp = shelf['x']
tmp.append('z')
shelf['x']=tmp
print(shelf['x'])
shelf.close()
#-------------------------输出结果----------------------------------#
"""
C:\python3.7\python.exe D:/Python-Test/qiubai/qiubai/Test8.py
['a', 'b', 'c']
['a', 'b', 'c', 'z']
"""

#简单的数据库示例
import shelve,sys

def db_store(db):
    "存储"
    pid = input("please input your num:\n")
    person={}
    person['name'] = input("please input your name:\n")
    person['age']=input("please input your age:\n")
    person['phone']=input("please input your phone:\n")
    db[pid]= person

def db_lookup(db):
    "查找"
    pid = input("please input your id num:")
    field = input("would you want to know name age or phone:")
    field = field.strip().lower()#用户可以随意输入大小写和空格
    print(field.capitalize() + ':' + db[pid][field])

def prin_cmd():
    print("*"*15)
    print("store:存储")
    print("lookup:查找")
    print("quit:退出")
    print("?:帮助")
    print("*" * 15)

def enter_cmd():
    cmd = input("? for help:\n")
    cmd = cmd.strip().lower()
    return cmd

def main():
    database = shelve.open("db_person.txt")#主程序打开数据库shelf然后作为参数传给其它函数
    try:
        while True:
            cmd = enter_cmd()
            if cmd == 'store':
                db_store(database)
            elif cmd == 'lookup':
                db_lookup(database)
            elif cmd == '?':
                prin_cmd()
            elif cmd == 'quit':
                return
    finally:#保证数据库关闭
        database.close()
if __name__ == '__main__':
    main()

#-------------------------输出结果----------------------------------#
"""
C:\python3.7\python.exe D:/Python-Test/qiubai/qiubai/Test8.py
? for help:
stroe
? for help:
store
please input your num:
2
please input your name:
lisi
please input your age:
23
please input your phone:
132
? for help:
store
please input your num:
3
please input your name:
adjf;as
please input your age:
23
please input your phone:
23423
? for help:
lookup
please input your id num:2
would you want to know name age or phone:name
Name:lisi
? for help:
?
***************
store:存储
lookup:查找
quit:退出
?:帮助
***************
? for help: