Singleton pattern in python

Context

python 레포 피쳐 개발하다가, 너무 오랜만에 이 개념을 봐서 복습.

What I Learned

The Singleton Pattern ensures a class has only one instance throughout a program and provides a global access point.

It is commonly used for managing shared resources like databases, logging systems or file managers.

All Python modules are singletons by default. Any variables or functions defined in a module are shared across imports.

Code

class Single:
    instance = None

    def __new__(cls):
        if cls.instance is None:
            cls.instance = super().__new__(cls)
        return cls.instance


a = Single()
b = Single()

print(a is b)

Note

put the definition to the name and try not to forget