How to declare static variable in python

static.py

class Parent:      # define parent class
   parentAttr = 100   # Static variable or class variable declaration
   def __init__(self):
      print ("Calling parent constructor")

   def parentMethod(self):
      print ('Calling parent method')
      
# Set Class or static variable 'parentAttr'
   def setAttr(self, attr):
      Parent.parentAttr = attr                      

   def getAttr(self):
      print ("Parent attribute :", Parent.parentAttr)

class Child(Parent): # Inherite parent class attribute by child class
   def __init__(self):
      print ("Calling child constructor")

   def childMethod(self):
      print ('Calling child method')

c = Child()          # instance of child
c.childMethod()      # child calls its method
c.parentMethod()     # calls parent's method
c.setAttr(200)       # again call parent's method
c.getAttr()          # again call parent's method