python learning curve

/wKiom1lSGiugoX3pAAK4fm_C49Y652.png-wh_ 500x0-wm_3-wmp_4-s_1691709091.png "title=" 6.png "alt=" wkiom1lsgiugox3paak4fm_c49y652.png-wh_50 "/> #!/usr/bin/envpython#-*-coding:utf-8-*-#author:flyfishage_of_zhangyy =26count=0whilecount650) this.width=650; "Src=" https://s5.51cto.com/wyfs02/M01/9A/28/wKiom1lSGufCIjKrAAOJa8UsP84766.png-wh_500x0-wm_ 3-wmp_4-s_331479539.png "title=" 7.png "alt=" Wkiom1lsgufcijkraaoja8usp84766.png-wh_50 "/>Three: Python's module knowledge:Python's strength is that he has

empty.When not empty, you can write a module import statement under a package in a file, because the __init__.py file is imported when the module is actually imported.3. Import Module Statement formatImport Module NameFrom Package name Import module name (only one module in the package is imported)From package name. module Name Import function name (when a specific function in the module needs to be imported)4..pycache fileThe module is executed when it is imported, and the

$1000000.‘As you may have guessed, the % operator is used to format the string. Inside the string, the representation is replaced by a string, which %s %d is replaced with an integer, there are several %? placeholders, followed by a number of variables or values, the order to correspond well. If there is only one %? , the parentheses can be omitted.Common placeholders are:%d 整数%f 浮点数%s 字符串%x 十六进制整数where formatted integers and floating-point numbers can also specify whether to complement 0 a

(Self.name)8 9 defstaticprint ():Ten Print('This class\ ' s name was person')The next step is to create a new instance of the class and call it.1 Instance=person ('Tom')2instance.printname () 3 person.staticprint ()The first line invokes the constructor of the person and assigns the instance to the instance variable. It is worth noting that there is no new keyword in python.The second line invokes the instance method of the Printname. Output Tom.The third line invokes the Staticprin

the returned string is more friendly to the end user.If you only want to implement one of these two special methods, __repr__ is a better choice, if an object does not have a __str__ function, and Python needs to call it, the interpreter uses __repr__ insteadA custom Boolean valueBy default, instances of our own defined classes are always considered true unless the class has its own implementation for __bool__ or __LEN__ functions. The result of x.__

Python statementAssignment statements1. Assign the 3 object to the variable a2, 3, 4 is assigned to the variable, a, b1 >>> a = 3 2 >>> A, B = 3,43 >>> a4 35 >>> b6 47 >>> a = 3,48 >>> a9 (3, 4)3, the realization will a,b=3,4 exchange a,b=4,31>>> b =3,4 Generally we declare a temporary variable to resolve2>>> temp =a3>>> A =b4>>> B =Temp5>>>a647>>>b839>>> b,a=This can be done in Python, because the va

: Let the adorner with class parameters Nineth Step: Adorner with class parameters, and split the public class into other py files, but also demonstrates the application of a function of multiple adorners #-*-CODING:GBK-*-' mylocker.py: public class for example 9.py ' class Mylocker:def __init__ (self):p rint ("mylocker.__init__ () Called. ") @staticmethoddef acquire ():p rint ("Mylocker.acquire () called.") @staticmethoddef unlock ():p rint ("Mylocker.unlock () called.") Class Lockerex (Myloc

multithreaded here Pool.submit (Async_url, URL) # Async_url is a method, URL is passed past parameters Pool.shutdown () # Close ProcessAsynchronous Io_1---asyncio module (no-http)Python Learning async for---io [asyncio module (no-http)]Asynchronous Io_2---gevent+grequestsPython learns asynchronous---io [gevent+grequests module]Asynchronous Io_3---Twisted modulePython learns asynchronous---io [twisted m

does not error, it returns none.Has_key: Checks whether the dictionary contains the given key. The expression D.has_key (k) is equivalent to K in D. Items and iteritems: Items return a dictionary item as a list, iteritems and items work the same, but it returns an iterator object instead of a list.keys and Iterkeys: The Keys method returns the keys in the dictionary as a list, and the Iterkeys method returns the values in the dictionary as a listpop: Gets the value corresponding to the given ke

Python engineer learning tour: python engineer tour 1. Python software development Basics 1. linux operating system 2. docker basics 3. python basic syntax 4. python String Parsing 5. python