Python keywords are reserved words with predefined meanings and purposes in the Python programming language. These words form the syntax and structure of Python programs and cannot be used as identifiers (like variable names, function names, etc.).

What Are Python Keywords?

Keywords are case-sensitive and are always written in lowercase. Python 3.11 currently has 36 keywords, though this number may vary with future updates. Examples include if, else, for, while, def, return, etc.

You can view all Python keywords in your environment using the following command:

import keyword
print(keyword.kwlist)

Output

['False', 'None', 'True', 'and', 'as', 'assert', 'async', 'await', 'break', 'class', 'continue', 'def', 'del', 'elif', 'else', 'except', 'finally', 'for', 'from', 'global', 'if', 'import', 'in', 'is', 'lambda', 'nonlocal', 'not', 'or', 'pass', 'raise', 'return', 'try', 'while', 'with', 'yield']

Python Keywords with Examples

False, True

These represent Boolean values.

is_active = True
is_logged_in = False
print(is_active and not is_logged_in) # Output: True

None

Represents the absence of a value.

def greet():
    pass # No implementation yet

result = greet()
print(result) # Output: None

and, or, not

Logical operators.

x = 10
y = 20

if x > 5 and y > 15:
    print("Both conditions are True")

if x > 15 or y > 15:
    print("At least one condition is True")

if not (x > 15):
    print("Condition is False")

as

Used for creating an alias while importing modules.

import math as m
print(m.sqrt(16)) # Output: 4.0

assert

Used for debugging.

x = 10
assert x > 5, "x must be greater than 5"
assert x < 5, "x must be less than 5" # This will raise an AssertionError

async, await

Used for asynchronous programming.

import asyncio

async def main():
    print("Hello")
    await asyncio.sleep(1)
    print("World")

asyncio.run(main())

break, continue

Control flow keywords in loops.

for i in range(5):
    if i == 3:
        break
    print(i) # Output: 0, 1, 2

for i in range(5):
    if i == 3:
        continue
    print(i) # Output: 0, 1, 2, 4

class

Defines a class.

class Person:
    def __init__(self, name):
        self.name = name

person = Person("Infovistar")
print(person.name) # Output: Infovistar

def

Defines a function.

def add(a, b):
    return a + b

print(add(2, 3)) # Output: 5

if, elif, else

Conditional statements.

x = 10
if x > 15:
    print("Greater than 15")
elif x == 10:
    print("Equal to 10")
else:
    print("Less than 10")

for, while

Loops for iteration.

# for loop
for i in range(3):
    print(i) # Output: 0, 1, 2

# while loop
count = 0
while count < 3:
    print(count)
    count += 1 # Output: 0, 1, 2

Python keywords form the foundation of any Python program. By understanding and using them effectively, you can write clear and efficient Python code. Make sure to stay updated with changes in the Python language to keep your knowledge fresh.