Creation of object and SINGLETON

Conceptually, we use __new__ when you need to control the creation of a new instance and use __init__ when you need to control initialization of a new instance.

# Python program to
# demonstrate __new__

# don't forget the object specified as base
class A(object):
    def __new__(cls):
        print("Creating instance")
        result = super(A, cls).__new__(cls)
        return result

    def __init__(self):
        print("Init is called")

obj = A()
Creating instance
<class '__main__.A'>
<__main__.A object at 0x7f67cadd2748>
Init is called
<__main__.A object at 0x7f67cadd2748>
class Logger(object):
    def __new__(cls, *args, **kwargs):
        if not hasattr(cls, '_logger'):
            cls._logger = super(Logger, cls
                    ).__new__(cls, *args, **kwargs)
        return cls._logger