os of common Python modules

os.getcwd() Return the absolute path to the current working directory Python 3.7.0 (v3.7.0:1bf9cc5093, Jun 27 2018, 04:59:51) [MSC v.1914 64 bit (AMD64)] on win32 Type "copyright", "credits" or "license()" for more information. >>> import os >>> print(os.getcwd()) C:\Users\28914\AppData\Local\Programs\Python\Python37 os.chdir( ...

Posted by tony_l on Wed, 20 Nov 2019 21:12:02 -0800

python-selenum3 day 6 - WebDriver common API s

1. Loop through all drop-down list values2. Radio drop-down list3. Selection and cancellation of multi selection list4. Operate the radio box, multi box, assert and select all5. Assert keywords in page source code6. screenshots7. Drag page elements 1. Loop through all drop-down list values <!--Practicing html--> //Education back ...

Posted by pillot1005 on Wed, 20 Nov 2019 12:24:42 -0800

Linux deleted python by mistake, resulting in the unavailability of yum. Delete the reinstallation method.

Linux system is CentOS Linux release 7.4.1708 Python is deleted by manual, manual, and manual, which makes yum unavailable. Baidu, after reinstalling yum and python, always reported all kinds of errors. After suffering, I finally summed up a set of personal tests, which can be used and shared. Uninstall existing python firs ...

Posted by stereo on Wed, 20 Nov 2019 09:48:02 -0800

Python Basics - functions

A function, also known as a method, is a piece of code used to implement a specific functionFunction to improve code reusabilityFunction must be called to executeThe variables defined in the function are local variables. Local variables can only be used in the function and cannot be used outside the functionA function does only one thing import ...

Posted by Riparian on Wed, 20 Nov 2019 07:27:11 -0800

The use of Pyyaml module in Python

I. what is YAML YAML is a special language for writing configuration files, which is far more convenient than JSON format. The design goal of YAML is to facilitate human reading and writing. YAML is a lighter file format than XML and JSON, and it's simpler and more powerful. It can express structure through indentation. Does it sound like a ...

Posted by agnalleo on Wed, 20 Nov 2019 04:46:16 -0800

Node.js Asynchronous Programming Evolution Theory

This article uses the "Signature 4.0 International (CC BY 4.0)" license agreement, and welcomes reprinting, or re-modifying the use, provided the source is indicated. Signature 4.0 International (CC BY 4.0) Node.js asynchronous programming callback We know that there are two ways to handle events in Node.js, callback and EventEmitter. ...

Posted by isedeasy on Tue, 19 Nov 2019 20:15:42 -0800

Python notes: observer mode

In the observer pattern, the subject object generally has a core service that other services depend on, and maintains a list of other objects that depend on this core service (that is, the list of observers or monitors). When the subject object changes, the observer should change his or her state or perform some operations Three roles in the o ...

Posted by fnairb on Tue, 19 Nov 2019 11:42:17 -0800

django sets cookie s and session s

1 set cookie s In this case, the application name is cookie Model model from django.db import models from django.db import models class UserInfo(models.Model): username = models.CharField(max_length=64) password = models.CharField(max_length=64) Database migration python manage.py makemigrations python manage.py migrate ...

Posted by BlueGemini on Tue, 19 Nov 2019 08:19:28 -0800

Django framework 5-cookie s and session s

Why do we have cookie s and session s? Browser sends http request to server, establishes session, server returns complete, session ends, browser and service disconnect Send the http request again and establish the session again. The user information will be lost. The server cannot distinguish the requested information. A login account. After t ...

Posted by NINTHTJ on Tue, 19 Nov 2019 07:26:37 -0800

Blueprint in Flask

Catalog 1. Overview of flask blueprint 2. A simple blueprint implementation 2.1 example 1: 2.2 example 2: 3. Blueprint to realize the addition, deletion, modification and search of student information 3.1 view student information: 3.2 student information update: 3.3 increase ...

Posted by FD_F on Mon, 18 Nov 2019 23:51:34 -0800