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Python 3.x study notes 7 (module), python3.x 1. Definition:Module: Used to logically organize python code (variables, functions, classes, and logic: implement a function). The essence is the python file ending with. py.Package: Used to logically organize modules. In essence, a directory (must contain a _ init _. py fil

The original love coding, will program the nuclear power engineer. Personal blog Address: zhihu.com/people/zhong-yun-75-63Learn some tricks to maximize the performance of Python programs and avoid unnecessary waste of resources.1. Using Local variablesTry to use local variables instead of global variables: Ease of maintenance, improved performance, and memory savings.Use local variables to replace variables in the module namespace, such as ls = Os.lin

Python + Selenium notes (7): WebDriver and WebElement, (1)WebDriver WebDriver provides many functions and settings for interacting with browsers. Through WebDriver functions and some methods, it can interact with browser windows, warnings, frameworks, and pop-up windows, it also provides automated browser navigation, setting cookies, screenshots, and other features to facilitate our testing. (

Output: ++++++++++++ ++++++++++++1 Print("+++++++++++")2 Print("+ +")3 Print("+++++++++++")4 5 6 Print("+"*11)7 Print("+"+" "*9+"+")#Plus a plus space multiplied by nine plus a plus sign8 Print("+"*11)Small essay:# notation 1: direct with \ n line, output three times# string \ n is line breakThe # string \ t is an indent symbol, each indent symbol is a eight-space position1 #have () line break, can

Locally compiled open vswitch times wrongtraceback (Mostrecentcalllast):file "./ovsdb/ovsdb-idlc.in", line 8,inCan be roughly judged because Python lacks a component bugThe workaround is to install it manually:Yum Install-y python-sixDownload path: http://mirrors.163.com/centos/7/os/x86_64/Packages/python-six-1.9.0-

Concise Python tutorial --- 7. Functions A function is a reusable statement block. Many languages allow defining functions to specify a name for a statement block, and reuse the statement block countless times in other places of the program. In python, the def keyword is used to define functions. The def keyword is followed by the function name, followed by a pa

',' aaa ',' e ',' great '] 2: #lis. Remove (' value ') 3: #如果不存在则发生异常: 4: #Traceback (most recent): 5: # in 6: # Lis.remove (' value ') 7: In list 8: lis.remove (' a ') 9: ' great '] Ten: lis.remove (' e ') One: : Print Lis8, List.reverse (): In-situ flip list 1: lis = [1,2,3,4,' a ',' B ',' C ',' a ',' aaa ',' e ',' great ']

， 　　Six. Dedicated underline identifiers 1234567891011121314151617181920212223242526272829 _xxx:不能用frommoduleimport*导入__xxx__:系统定义名字__xxx:类中私有变量下划线对于解释器来说有特殊意义，而且是内建标识符所使用符号，不建议自定义变量以下划线开头但是如果是类中的私有变量，__xxx将会是一个好习惯系统变量__name__会根据python文件被加载方式的不同得出不同的值。 　　　　python文件被当作模块导入：__name__=模块名或者文件名　　　　python文件被执行:__name__=‘__main__‘在我们使用

draftsURL2 = "Https://i.cnblogs.com/EditPosts.aspx?opt=1"BODY = {"__viewstate": "","__viewstategenerator": "fe27d343","Editor$edit$txbtitle": "This is my title: Shanghai-Leisurely","Editor$edit$editorbody": ""Editor$edit$advanced$ckbpublished": "On","Editor$edit$advanced$chkdisplayhomepage": "On","Editor$edit$advanced$chkcomments": "On","Editor$edit$advanced$chkmainsyndication": "On","Editor$edit$lkbdraft": "Save as draft",}r2 = S.post (Url2, Data=body, Verify=false)# Get the current URL addres

;> X.bit_length (117)6. Mathematical operations of complex numbers Complex numbers can be specified by using Functions complex (real, imag) or floating-point numbers with suffix J >>>a=complex (2,4) >>>b=3-5j>>>a (2+4j) > >>b (3-5j) corresponding to the real, imaginary and conjugate complex >>>a.real2.0>>>a.imag4.0>>> A.conjugate () (2-4j) All common mathematical operations can work >>>a+b (5-1j) >>>a-b

... ' )56 def TearDown (self):7 Print ('tearDown ... ')Four: Document testing (Python's built-in "Document Test" (doctest) module extracts the code directly from the comment and executes the test. ）1 #mydict2.py2 classDict (Dict):3 " "4 Simple Dict-also support access as x.y style.5 6 >>> D1 = Dict ()7 >>> d1[' x '] =8 >>> d1.x9 -Ten >>> d1.y = One >>> d1[' y '] A $ - >>> d2 = Dict (A=1,

first day. N=1 for in range (5,0,-1= (n+1) print(n)6, Healthy recipes output. List of 5 different ingredients, please print out what they may consist of There is a dish name. Diet = ['Tomato','Broccoli','Cucumber','Steak','Shrimp'] forXinchRange (0,5): forYinchRange (0,5):if not(x==y):Print("{}{}". Format (Diet[x],diet[y]))7. The drawing of the pentagram. draw a red pentagram graphic. from Import*fillcolor ("red") Begin_fill () while True: Forwa

Python growth path Article 3 (2) _ regular expressions, the path to python GrowthAdd an advertisement. Welcome to linux. python Resource Sharing Group No.: 478616847. directory: 1. What is a regular expression? introduction to regular expressions in python2. re Module Content3. Small exercises1. What is a regular expre

Download Link: http://www.jetbrains.com/pycharm/If only to develop Python, this free version should have been enough.Today's talk is how to install Pycharm under CentOS7:Download complete, right-click Extract here can be extracted;Decompression completed, into the bin directory, right-click terminal;chmod +x pycharm.sh Let this file have permission to run;Su can enter root before running, otherwise the installation may not succeedTerminal./pycharm.sh

In Python programming, the most common types of collections we use are: list,tuple,set,dict; let's talk about these types of collections in a few simple ways;List lists: Equivalent to an array, but the length of the list is automatically changed and the elements are free, without having to be the same type for each element. Its concise definition is a=[]. is an ordered combination of elements that can be deleted and added;The basic operations of the l

= a.isdisjoint (b) print (t)#a. Issubset (b) A is not a sub-sequence of bPrint (A.issubset (b))#a. Issuperset (b) is not the parent sequence of BPrint (A.issuperset (b))#a. Pop () to remove an element, you can assign the removed value to a variableTa = A.pop () print (TA)#练习: Look for differences and update the old dictionaryUpdates that are present in the #将old_dict, new_dict, old_dict deletions that do not exist in New_dict#new_dict在old_dict中不存在的, append to old.Old_dict = { "#1": {' hostna

Python learning-stage Comprehensive Exercises 2. python Comprehensive Exercises Based on the previous class learning, do the following example exercises: (do not read the code first, and try to write the code first. The code is for reference only. There are multiple implementation methods) 1. Triangle Equilateral 1) create a class Triangle to indicate a Triangl

The Python 2 and Python 3 codes are:1 #_*_coding:utf-8_*_2 #__author__ = "Csy"3 4 classA:5 def __init__(self):6 Print("A")7 8 classB (A):9 PassTen #def __init__ (self): One #print ("B") A - classC (A): - def __init__(self): the Print("C") - - classD (b,c): - Pass + #def __i

11. Object-Oriented Programming(1) IntroductionSlightly(2) SelfSuppose you have a class called MyClass and an instance of this class MyObject .When you call the method MyObject.method(arg1, arg2) of this object,This will be automatically converted MyClass.method(MyObject, arg1, arg2) by Python-that's how it self works .(3) classSlightly(4) Methods of the objectSlightly(5) __init__ methodSlightly(6) Var

. PopitemThe Popitem method is similar to List.pop, which pops up the last element of the list. But the difference is that popitem pops up random entries because the dictionary does not have "last element" or other concepts about the order. This method works well if you want to remove and process items one after the other, because you don't have to get the list of keys first.The dictionary does not have a method equivalent to append, because the dictionary is unordered, and a method similar to a