Singleton Design Pattern

Global State and Singleton cause the code hard to test youtube To use DI as possible.

test

add a .replit file with the following lines

language = "python3"
run = "python -m unittest discover -v"

decorator way of doing this

def singleton(class_):
    instances = {}
    def getinstance(*args, **kwargs):
        if class_ not in instances:
            instances[class_] = class_(*args, **kwargs)
        return instances[class_]
    return getinstance

@singleton
class MyClass(BaseClass):
    pass

*There are may other ways, refer to here in stackoverflow

try another way of implementation

https://github.com/tylerlaberge/PyPattyrn#singleton-pattern