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Why is __init__() always called after __new__() in python?
Python is having special type of methods called magic methods named with preceded and double underscores.
if we want to talk about magic method __new__ then obviously will also need to talk about __init__ method. The magic method __new__ will be called when instance is being created.where as __init__ method will be called to initialize instance when you are creating instance.
Example
class X(): _dict = dict() def __new__(self): if 'data' in X._dict: print ("new instance Exists") return X._dict['data'] else: print ("magic method New") return super(X, self).__new__(self) def __init__(self): print ("instantiation") X._dict['data'] = self print ("") a1 = X() a2 = X() a3 = X()
Output
magic method New instantiation new instance Exists instantiation new instance Exists instantiation
important to remember : The __init__ function is called a constructor, or initializer, and is automatically called when you create a new instance of a class.
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