Python - __init__ 参数

Question

I have the following problem.

class Operacoes(object):

    def __init__(self, *args):
        self.__numero = args

    def get_numero(self) -> int:
        return self.__numero

x = Operacoes(10).get_numero()
print(x)
#(10,)

This is making me very intrigued, why does anyone know how to tell me?

args, should return an int in case number 10, but a Tuple is returning.

Answer 1

It is because when you call the get_numero() method, self.__numero is returned. And when looking at self.__numero in __init__() , it is returning args , which is always a Tuple, even if you have only 1 argument.

Answer 2

Let's look closer at the syntax. You assigned

*args = 10

The star is really important here because it does unpacking of a tuple/list. By Python specification args is a tuple, even if it contains a single element.

Then, self.__numero stores a tuple. When you retrieve it and print it, it is still a tuple.