Recalling the last lesson
os module
Interact with the operating system
sys module
Interact with the python interpreter
json module
Cross-platform data exchange, json string
pickle module
Python interactive store all types of data, in order to python file and python files
logging module
Logging
Today plant science
package
- == module package, the package is brought introduction
- Package containing
__init__.pythe folder; leader packet is introduced__init__ - Packet must be treated as module file import file search path module m1.py/m2.py execution file path to prevail
time module
Offers three different types of time (for the most important time stamp), three different types of time can be interchangeable
# 时间戳形式
print(time.time())
# 格式化时间
print(time.strftime('%Y-%m-%d %X'))
# 结构化时间
print(time.localtime())time.sleep () allow a program to sleep for a few seconds
datetime module
Time of addition and subtraction
import datetime
now = datetime.datetime.now()
print(now)
# 默认3天
print(now + datetime.timedelta(3))
# 加3周
print(now + datetime.timedelta(weeks=3))
# 加3小时
print(now + datetime.timedelta(hours=3))
# 减3小时
print(now - datetime.timedelta(hours=3))random module
random number
random.random()
0-1 specific number
random.randint(1,3)
Integer 1-3
lt=[1,2,3]
random.shuffle(lt)# 打乱列表
random.choice(lt)# 随机选择一个random.seed()
Only a random
hashlib module and the module hmac
hashlib module
encryption
m = hashlib.md5()
m.update(b'hello')
m.update(b'hello')
print(m.hexdigest())
m = hashlib.md5()
m.update(b'hellohello')
print(m.hexdigest())- Results are always the same length of the string
- Superposition
hmac module
Encryption, salt processing
m = hmac.new(b'123')
m.update(b'hellow')
print(m.hexdigest())typing module
A function associated with the control function parameter data type, a data type other than the type of underlying data
requests module
Reptiles generally used for crawling data, the browser get analog data transmission request url
#用法
import requests
res=requests.get(url)
data=res.text
print(data)re module
String to find String meet certain characteristics
```python
Find all
findall
^: ... begins with
res = re.findall('^ab', s)
print(res)
res = re.findall('^bc', s)
print(res)
$: Ends with ..
s = 'abcdabc'
res = re.findall('bc$', s)
print(res)
: Any character
s = 'abc红abc'
res = re.findall('abc.', s)
print(res)
\ D: Digital
s = 'skld2342ljk'
res = re.findall('\d', s)
print(res)
\ W: non-empty, alphanumeric underscore
s = 'skld_23 42ljk'
res = re.findall('\w', s)
print(res)
\ S: empty spaces / \ t / \ n
s = 'skld_23 42ljk'
res = re.findall('\s', s)
print(res)
\ D: Non-digital
s = 'skld2342ljk'
res = re.findall('\D', s)
print(res)
\ W: Empty
s = 'skld_23 42ljk'
res = re.findall('\W', s)
print(res)
\ S: non-empty
s = '