In everyday Python programming, we just override the _init_ method to assign values to the object that was already created earlier by the default _new_ behaviour. I think it is very rare to override _new_ because its default behaviour, which is to create an empty instance of the particular class, is usually what we want. So _new_ is the constructor: Its job is to build a new instance object using the class as a template. _init_ is used to then initialize the properties of the instance that was created by _new_. Technically the _new_ method takes a class and generates an instance of that class. Here is an example to restrict a class to have only four instances. We can inherit from our previous class Point (first example in this article) and use new() to implement this restriction. Suppose we want to make a class RectPoint for creating instances to represent the four vertices of a square. Some practical use of _new_() can be to restrict the number of objects created from a class, make a singleton and return a completely different object at the end. You would have seen _init_() being used more frequently than _new_() as we mostly need to initialize objects not how the object is controlled though we can use _new_() to initialize objects but it will make more sense to initialize them in _init_(). In the above example, we have done this using super(). In Python, object is the base class from which all other classes are derived. Finally, the object is created by calling the _new_() method on object base class. We see that _new_() is called before _init_() when an object is initialized and can also see that the parameter cls in _new_() is the class itself (Point). Enter fullscreen mode Exit fullscreen mode
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