Avoid if __name__ == '__main__' in Python subclasses to be run using function from parent

I have a generic class (A) which is to be subclassed a lot like this:

class A:
    def run(self):
        ...
        self.do_something()
        ...

    #abstract function
    def do_something(self):
        pass


class B(A):
    def do_something(self):
        ...

The subclasses are in separate files that I'm running directly by adding this code to each file (B is the name of the subclass in the file):

if __name__ == '__main__':
  开发者_运维百科  B().run()

My question is, can I avoid having to add this code to all files with the subclasses since the only thing that changes in the code is the class being used (B in the example)?

---

If your python version is recent enough, you can create a class decorator.

In this case, an indirect one.

def runifmain(mainname):
    def deco(clas):
        if mainname == '__main__':
            clas().run()
        return clas
    return deco


@runifmain(__name__)
class B(A):
    [...]

should do the job if you define runifmain() somewhere centrally and just use the @runifmain(__name__)wherever it is needed.

---

What about adding an extra function to your main class A?

class A():
    ..
    def __RunIfMain__(self,name):
        if name == '__main__':
            self.run()

In your subclass you'd have one line less:

class B(A):
  ..

B().__RunIfMain__(__name__)