python模块汇总练习

# print(random.random())
# print(random.randint(1,3))

#模拟随机验证码
def make_code(n=5):
    res=‘‘
    for i in range(n):
        s1=str(random.randint(0,9))
        s2=chr(random.randint(65,90))
        res+=random.choice([s1,s2])
    return res
print(make_code(10))

 1 num=30
 2 print(‘%s%%‘%num)
 3 
 4 #打印进度条
 5 width=50
 6 print((‘[%%-%ds]‘%width)%‘#‘)
 7 print((‘[%%-%ds]‘%width)%‘##‘)
 8 print((‘[%%-%ds]‘%width)%‘###‘)
 9 print((‘[%%-%ds]‘%width)%‘####‘)
10 
11 def progress(percent,width=50):
12     if percent > 1:
13         percent=1
14     show_str=((‘[%%-%ds]‘%width)%(int(width*percent)* ‘#‘))
15     print(‘\r%s %d%%‘%(show_str,int(100*percent)),end=‘ ‘)
16 
17 import time,random
18 recv_size=0
19 total_size=8097
20 while recv_size<total_size:
21     time.sleep(0.5)
22     recv_size+=1024
23     percent=recv_size / total_size
24     progress(percent)

 1 import shelve
 2 
 3 #序列化
 4 info1={‘age‘:18,‘herght‘:180,‘weight‘:80}
 5 info2={‘age‘:88,‘herght‘:150,‘weight‘:80}
 6 
 7 d=shelve.open(‘db.shv‘)
 8 d[‘egon‘]=info1
 9 d[‘alex‘]=info2
10 d.close()
11 
12 #反序列化
13 d=shelve.open(‘db.shv‘)
14 print(d[‘alex‘])
15 print(d[‘egon‘])
16 d.close()
17 
18 
19 #修改数据
20 d=shelve.open(‘db.shv‘,writeback=True)
21 # d[‘alex‘][‘age‘]=10000
22 print(d[‘alex‘])
23 d.close()

 1 import xml.etree.ElementTree as ET
 2 tree=ET.parse(‘a.xml‘)
 3 root=tree.getroot()
 4 
 5 #========================================》》查
 6 #三种方式查找节点
 7 res=root.iter(‘rank‘)#会在整个树中进行查找，而且是查找所有
 8 for item in res:
 9     # print(item)
10     print(‘=‘*50)
11     print(item.tag)#标签名
12     print(item.attrib)#属性
13     print(item.text)#文本内容
14 
15 
16 res=root.find(‘country‘)#只能在当前元素的下一级进行查找，并且只找到一个就截止
17 # print(res.tag)
18 # print(res.attrib)
19 # print(res.text)
20 n=res.find(‘rank‘)
21 print(n.attrib)
22 
23 
24 
25 res=root.findall(‘country‘)#只能在当前元素的下一级进行查找,
26 print([item.tag for item in res])
27 
28 
29 
30 #=====================================》》改
31 import xml.etree.ElementTree as ET
32 tree=ET.parse(‘a.xml‘)
33 root=tree.getroot()
34 
35 for year in root.iter(‘year‘):
36     year.text=str(int(year.text)+10)
37     year.attrib={‘updated‘:‘yes‘}
38 tree.write(‘a.xml‘)
39 
40 
41 
42 #===============================》增
43 import xml.etree.ElementTree as ET
44 tree=ET.parse(‘a.xml‘)
45 root=tree.getroot()
46 
47 for country in root.iter(‘country‘):
48     # print(‘year‘)
49     year=country.find(‘year‘)
50     # print(year)
51     if int(year.text) > 2010:
52         # print(country.attrib)
53         # ele=ET.Element(‘egon‘)
54         # ele.attrib={‘nb‘:‘yes‘}
55         # ele.text=‘好‘
56         # country.append(ele)
57         country.remove(year)
58 
59 tree.write(‘b.xml‘)