Python学习第十五天

#!/usr/bin/python

#filename:test15.py

import struct

with open('myfile.zip','rb') as f:

data = f.read()

# print(data)

start = 0

for i in range(2):

start += 14

fields = struct.unpack("<IIIHH",data[start:start+16])

crc32,comp_size,uncomp_size,filenamesize,extra_size = fields

start += 16

filename = data[start:start+filenamesize]

start += filenamesize

extra = data[start:start+extra_size]

print(filename,hex(crc32),comp_size,uncomp_size)

start += extra_size + comp_size

import threading,zipfile

class AsyncZip(threading.Thread):

def __init__(self,infile,outfile):

threading.Thread.__init__(self)

self.infile = infile

self.outfile = outfile

def run(self):

f = zipfile.ZipFile(self.outfile,'w',zipfile.ZIP_DEFLATED)

f.write(self.infile)

f.close()

print('Finished backgroud zip of:',self.infile)

background = AsyncZip('mydata.txt','myarchive.zip')

background.start()

print('The main program continues to run in foreground.')

background.join()

print('Main program waited until background was done.')

import logging

logging.debug('debugging information')

logging.info('informational message')

logging.warning('Warning:config file %s not found','server.conf')

logging.error('Error occurred')

logging.critical('Critical error -- shutting down')

import weakref,gc

class A:

def __init__(self,value):

self.value = value

def __repr__(self):

return str(self.value)

a = A(10)

d = weakref.WeakValueDictionary()

d['primary'] = a

print(d['primary'])

del a 

gc.collect()

from array import array

a = array('H',[4000,10,700,22222])

print(sum(a))

print(a[1:3])

from collections import deque

d = deque(['task1','task2','task3'])

d.append('task4')

print('Handling',d.popleft())

import bisect

scores = [(100,'perl'),(200,'tcl'),(400,'lua'),(500,'python')]

bisect.insort(scores,(300,'ruby'))

print(scores)

from heapq import heapify,heappop,heappush

data = [1,3,5,7,9.2,4,6,8,0]

heapify(data)

heappush(data,-5)

[heappop(data) for i in range(3)]

from decimal import *

aa = round(Decimal('0.70')*Decimal('1.05'),2)

print(aa)

print(.70*1.05,2)

print(sum([Decimal('0.1')]*10))

print(sum([0.1]*10))