Setting a class variable as a default argument of a class method uses a class variable as an argument of a function in the class if no argument is given.
Solution for How to set a class variable as a default argument of a class method in Python : You can use a placeholder to set a class variable as a default argument of a class method Use the syntax class_method(self, arg=None) to set the default value of arg to None in the function class_method. If arg is None, assign arg to a class variable value with the syntax arg = self.value.
