how to call class in another class in python code example

Example 1: call a function from another class python

class A:
    def method1(arg1, arg2):
        # do code here

class B:
    A.method1(1,2)

Example 2: access class variable from another class python

class ClassA(object):
    def __init__(self):
        self.var1 = 1
        self.var2 = 2

    def methodA(self):
        self.var1 = self.var1 + self.var2
        return self.var1



class ClassB(ClassA):
    def __init__(self, class_a):
        self.var1 = class_a.var1
        self.var2 = class_a.var2

object1 = ClassA()
sum = object1.methodA()
object2 = ClassB(object1)
print sum