Python Statements

In Python, a statement is like a sentence in English—it tells the computer to do something. Let’s break it down into simple types of statements, with examples you can try.

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1. Expression Statements

An expression statement evaluates something and gives you a result. Think of it like solving a math problem.

Example:

# Expression statement
3 + 4

Output:

7

You don’t need to store the result; Python simply evaluates the expression.

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2. Assignment Statements

These are used to store values in variables. Think of variables as boxes where you can keep information.

Example:

# Assignment statement
x = 5
y = 10
sum_of_numbers = x + y
print(sum_of_numbers)

Output:

15

x = 5 assigns the value 5 to x. You can then use x in calculations.

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3. Conditional Statements

These allow your program to make decisions based on conditions. It’s like asking, “Is it raining? If yes, take an umbrella.”

Example:

# Conditional statement
temperature = 25

if temperature > 30:
    print("It's hot!")
else:
    print("It's a nice day!")

Output:

It's a nice day!

Python checks if temperature > 30. If it’s true, it runs the first print(); otherwise, it runs the second.

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4. Looping Statements

Loops are like repeating the same task until you’re done. For example, counting numbers.

Example: For Loop

# For loop
for number in range(1, 6):
    print(f"Number: {number}")

Output:

Number: 1
Number: 2
Number: 3
Number: 4
Number: 5

The loop starts at 1 and ends at 5, printing each number.

Example: While Loop

# While loop
count = 1
while count <= 5:
    print(f"Count is: {count}")
    count += 1

Output:

Count is: 1
Count is: 2
Count is: 3
Count is: 4
Count is: 5

The loop runs as long as count <= 5. After each iteration, count increases by 1.

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5. Function Definition Statements

Functions group code that performs a task. Imagine it as a machine where you input something, and it gives an output.

Example:

# Function definition
def greet(name):
    return f"Hello, {name}!"

print(greet("John"))

Output:

Hello, John!

The greet() function takes a name and returns a greeting message.

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6. Import Statements

Python has libraries (pre-built code) you can use. The import statement brings these into your program.

Example:

# Import statement
import math

result = math.sqrt(16)
print(f"The square root of 16 is {result}")

Output:

The square root of 16 is 4.0

The math library helps with advanced math operations.

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7. Try-Except Statements

These handle errors gracefully. Think of it as a safety net.

Example:

# Try-Except statement
try:
    number = int(input("Enter a number: "))
    print(f"You entered: {number}")
except ValueError:
    print("That's not a number!")

Output (if input is abc):

That's not a number!

If the input isn’t a number, the except block runs instead of crashing the program.

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8. Pass Statements

The pass statement does nothing—it’s a placeholder. It’s useful when you’re planning to write code later.

Example:

# Pass statement
if True:
    pass

Output:

No output—Python does nothing.

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9. Break and Continue Statements

These control how loops behave. break stops a loop, and continue skips to the next iteration.

Example: Break

for number in range(1, 10):
    if number == 5:
        break
    print(number)

Output:

1
2
3
4

The loop stops completely when number is 5.

Example: Continue

for number in range(1, 6):
    if number == 3:
        continue
    print(number)

Output:

1
2
4
5

The number 3 is skipped, but the loop continues.

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10. Return Statements

Used inside functions to send a result back.

Example:

# Return statement
def square(num):
    return num * num

result = square(4)
print(f"Square of 4 is {result}")

Output:

Square of 4 is 16

The return sends num * num back to where the function was called.

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Quick Summary Table

Type of Statement	Purpose	Example
Expression	Evaluate something	3 + 5
Assignment	Store values in variables	x = 10
Conditional	Make decisions	if x > 5:
Looping	Repeat tasks	for i in range(5):
Function Definition	Group code into a function	def add(a, b):
Import	Use external libraries	import math
Try-Except	Handle errors	try: ... except:
Pass	Do nothing temporarily	pass
Break/Continue	Control loop behavior	break, continue
Return	Return results from functions	return result