1. Membership Operators

1.1 Introduction

Membership operators are used to check whether a value exists in a sequence such as a string, list, tuple, set, or dictionary.

1.2 Types of Membership Operators

1.3 Using in Operator

text = "Python" print("P" in text)print("z" in text)

Output

TrueFalse

1.4 Using not in Operator

numbers = [1, 2, 3, 4] print(5 not in numbers)print(2 not in numbers)

Output

TrueFalse

1.5 Membership in Different Data Types

List

nums = [10, 20, 30]print(20 in nums)

String

print("Py" in "Python")

Dictionary

student = {"name": "Rahul", "age": 20} print("name" in student)

Explanation

• Checks keys, not values

1.6 Key Points

• Works with sequences and collections
• Checks presence of value
• Returns True or False
• In dictionaries, checks keys only

2. Identity Operators

2.1 Introduction

Identity operators are used to compare whether two variables refer to the same object in memory.

2.2 Types of Identity Operators

2.3 Using is Operator

a = 10b = 10 print(a is b)

2.4 Using is not Operator

x = [1, 2]y = [1, 2] print(x is not y)

2.5 Difference Between == and is

x = [1, 2]y = [1, 2] print(x == y) # compares valuesprint(x is y) # compares memory

Output

TrueFalse

2.6 Example with Same Object

a = [1, 2]b = a print(a is b)

Output

True

2.7 Key Points

• is checks object identity (memory location)
• == checks value equality
• Useful when comparing objects

3. Summary

Membership Operators

• Used to check presence of value
• Operators: in, not in
• Work with lists, strings, tuples, sets, dictionaries

Identity Operators

• Used to check object identity
• Operators: is, is not
• Compare memory locations, not values