Try–except–else behavior in Python - Mini Project: Build & Apply

Try-except-else behavior

📖 Scenario: Imagine you are writing a small program that divides numbers. Sometimes the user might enter zero as the divisor, which causes an error. You want to handle this error nicely and also do something special when there is no error.

🎯 Goal: You will create a program that tries to divide two numbers, catches division errors, and uses else to print a success message only when no error happens.

📋 What You'll Learn

Create two variables numerator and denominator with exact values

Create a variable result and set it to None

Use a try block to divide numerator by denominator and store in result

Use an except ZeroDivisionError block to set result to the string 'Cannot divide by zero'

Use an else block to print 'Division successful'

Finally, print the value of result

💡 Why This Matters

🌍 Real World

Handling errors like division by zero is common in calculators, data processing, and user input validation.

💼 Career

Understanding try-except-else helps you write robust code that doesn't crash and gives clear feedback, a key skill for any programmer.

1

Create numerator and denominator variables

Create a variable called numerator and set it to 10. Create another variable called denominator and set it to 2.

Python

# Your code here

Need a hint?

Use simple assignment to create the two variables with the exact numbers.

2

Create a result variable

Create a variable called result and set it to None.

Python

numerator = 10
denominator = 2
# Your code here

Need a hint?

Initialize result to None before the try block.

3

Write try-except-else to divide numbers

Write a try block where you divide numerator by denominator and assign it to result. Add an except ZeroDivisionError block that sets result to the string 'Cannot divide by zero'. Add an else block that prints 'Division successful'.

Python

numerator = 10
denominator = 2
result = None
# Your code here

Need a hint?

Use the exact keywords and variable names as shown. The else block runs only if no error happens.

4

Print the result

Write a print(result) statement to display the value of result.

Python

numerator = 10
denominator = 2
result = None
try:
    result = numerator / denominator
except ZeroDivisionError:
    result = 'Cannot divide by zero'
else:
    print('Division successful')
# Your code here

Need a hint?

The program should print Division successful first, then the number 5.0.