else and finally

else and finally

In this tutorial, we'll run code after success or cleanup code no matter what.

try / except can also use else and finally.

else runs only if no exception happened.

try:
    number = int("42")
except ValueError:
    print("Invalid number")
else:
    print("Conversion worked:", number)

Why Use else?

You could put everything in the try block, but else keeps successful follow-up code separate from risky code.

try:
    age = int(input("Age: "))
except ValueError:
    print("Invalid age")
else:
    print("Next year:", age + 1)

Only the conversion is risky. The success message belongs in else.

finally

finally runs no matter what:

try:
    number = int("hello")
except ValueError:
    print("Invalid number")
finally:
    print("Finished attempt")

Output:

Invalid number
Finished attempt

finally is often used for cleanup, such as closing files or network connections.

The Full Shape

try:
    risky_code
except SomeError:
    handle_error
else:
    run_if_successful
finally:
    always_run_this

You do not need all four parts every time. Most beginner code uses just try and except.

A Practical Example

try:
    number = int(input("Number: "))
except ValueError:
    print("That was not a number")
else:
    print("Squared:", number * number)
finally:
    print("Thanks for trying")

This separates the risky conversion, the error message, the successful calculation, and the final message.

Practice

Ask for a number. Use else to print the doubled value if conversion succeeds. Use finally to print "Done".