# -------------------------------------------------
# -- Object Oriented Programming => Polymorphism --
# -------------------------------------------------
n1 = 10
n2 = 20
print(n1 + n2)
s1 = "Hello"
s2 = "Python"
print(s1 + " " + s2)
print(len([1, 2, 3, 4, 5, 6]))
print(len("Osama Elzero"))
print(len({"Key_One": 1, "Key_Two": 2}))
class A:
def do_something(self):
print("From Class A")
raise NotImplementedError("Derived Class Must Implement This Method")
class B(A):
def do_something(self):
print("From Class B")
class C(A):
def do_something(self):
print("From Class C")
my_instance = B()
my_instance.do_something()