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If you want to get rid of the username field and use email as unique user identifier, you will have to create a custom User model extending AbstractBaseUser instead of AbstractUser. Indeed, username and email are defined in AbstractUser and you can't override them. This means you will also have to r...

Below you could find the table Employees with a reference to the table Cities. CREATE TABLE Cities( CityID INT IDENTITY(1,1) NOT NULL, Name VARCHAR(20) NOT NULL, Zip VARCHAR(10) NOT NULL ); CREATE TABLE Employees( EmployeeID INT IDENTITY (1,1) NOT NULL, FirstName VARCHA...

You can specify a column that contains dates so pandas would automatically parse them when reading from the csv pandas.read_csv('data_file.csv', parse_dates=['date_column'])

A recursive function is a function that calls itself in its definition. For example the mathematical function, factorial, defined by factorial(n) = n*(n-1)*(n-2)*...*3*2*1. can be programmed as def factorial(n): #n here should be an integer if n == 0: return 1 else: ...

Used to obtain the size in bytes for an unmanaged type int byteSize = sizeof(byte) // 1 int sbyteSize = sizeof(sbyte) // 1 int shortSize = sizeof(short) // 2 int ushortSize = sizeof(ushort) // 2 int intSize = sizeof(int) // 4 int uintSize = sizeof(uint) // 4 int longSize = sizeof(long) // 8 ...

C# has several operators that can be combined with an = sign to evaluate the result of the operator and then assign the result to the original variable. Example: x += y is the same as x = x + y Assignment operators: += -= *= /= %= &= |= ^= <<= >>=

For simple array comparison you can use JSON stringify and compare the output strings: JSON.stringify(array1) === JSON.stringify(array2) Note: that this will only work if both objects are JSON serializable and do not contain cyclic references. It may throw TypeError: Converting circular struct...

In the HTTP server code (e.g. server.js): const EventEmitter = require('events') const serverEvents = new EventEmitter() // Set up an HTTP server const http = require('http') const httpServer = http.createServer((request, response) => { // Handler the request... // Then emit an event...

FlashDevelop is a multi-platform open source IDE created in 2005 for Flash developers. With no cost, it's a very popular way to get started developing with AS3. To Install FlashDevelop: Download The Installation File and run the installer Once installation is complete, run FlashDevelop. On the ...

from http://flex.apache.org/doc-getstarted.html Download the SDK installer Run the SDK installer. The first question you will be asked is the installation directory. on a Mac, use /Applications/Adobe Flash Builder 4.7/sdks/4.14.0/ on a PC, use C:\Program Files(x86)\Adobe Flash Builder ...

Objective-C NSMutableAttributedString *attributeString = [[NSMutableAttributedString alloc] initWithString:@"Your String here"]; [attributeString addAttribute:NSStrikethroughStyleAttributeName value:@2 range:NSMakeRange(0, [attributeString length...

AEM can be installed as a standalone executable JAR file or through web application servers, such as JBoss and WebSphere, as a WAR file. Prerequisites AEM 6.2 needs at minimum the following in order to run Java Runtime Environment (JRE) 1.8x (64bit) 5GB of free disk space for installation 2GB...

{ "some_string": null, "ather_string": "something" } If we will use this way: JSONObject json = new JSONObject(jsonStr); String someString = json.optString("some_string"); We will have output: someString = "null"; So we need to...

Detailed instructions on getting braintree set up or installed.

A VectorDrawable should consist of at least one <path> tag defining a shape <vector xmlns:android="http://schemas.android.com/apk/res/android" android:width="24dp" android:height="24dp" android:viewportWidth="24.0" android:viewpor...

A <group> tag allows the scaling, rotation, and position of one or more elements of a VectorDrawable to be adjusted: <vector xmlns:android="http://schemas.android.com/apk/res/android" android:width="24dp" android:height="24dp" android:viewportWidth="24...

An AnimatedVectorDrawable requires at least 3 components: A VectorDrawable which will be manipulated An objectAnimator which defines what property to change and how The AnimatedVectorDrawable itself which connects the objectAnimator to the VectorDrawable to create the animation The following...

In AS3, display assets are not visible until they are added to the Display List. The AIR/Flash runtime has a hierarchical display structure (parent child relationship where children can have their own children), with the stage being the top level parent. To add something to the display list, you u...

The s interpolator allows the usage of variables within a string. val name = "Brian" println(s"Hello $name") prints "Hello Brian" to the console when ran.

Add an accessory view above the keyboard. This is commonly used for adding next/previous buttons, or additional buttons like Done/Submit (especially for the number/phone/decimal pad keyboard types which don't have a built-in return key). Swift let textField = UITextField() // initialized however ...