20.Write a Python program to using multiple inheritance.

class Class1:
    def msg1(self):
        print("In Class1")

class Class2(Class1):
    def msg2(self):
        print("In Class2")

class Class3(Class1):
    def msg3(self):
        print("In Class3")

class Class4(Class2, Class3):
    def msg(self):
        print("In Class4")

obj = Class4()
obj.msg1()

Reference

Multiple Inheritance When a class is derived from more than one base class it is called multiple Inheritance. The derived class inherits all the features of the base case.

https://www.geeksforgeeks.org/multiple-inheritance-in-python/