title: I've created a simple calculator in OOP way in python. I get an error message, that my variables are not defined
body: <p>So that's my calc, I was trying to do it to understand class decorators better</p>
  
  <pre><code>class Calc():
  
     @staticmethod
     def add(x, y):
         return x + y
  
    .
    .
    .
  
     @staticmethod
     def div(x, y):
         return x / y
  
     @staticmethod
     def get_numbers():
         num1 = int(input("Enter first number: "))
         num2 = int(input("Enter second number: "))
         return num1, num2
  
     @staticmethod
     def get_operator():
         operator = input('Please enter an operator (+, -, *, /): ')
      return operator
  
     @classmethod
     def calculate(cls):
         cls.get_numbers()
         cls.get_operator()
         if operator == '+':
             print(add(num1, num2))
         elif operator == '-':
             print(sub(num1, num2))
         elif operator == '*':
             print(mul(num1, num2))
         elif operator == '/':
             print(div(num1, num2))
  
  
  Calc.calculate()
  </code></pre>
  
  <p>When I run it, I get this: </p>
  
  <pre><code>Traceback (most recent call last):
    File "calc_feltoltesre.py", line 44, in &lt;module&gt;
       Calc.calculate()
    File "calc_feltoltesre.py", line 32, in calculate
       get_numbers()
   NameError: name 'get_numbers' is not defined
  </code></pre>
  
  <p>I have no idea, why the operator and num1 and num2 are not visible in the scope. </p>