Lesson 12 of 19
Exceptions
Handle errors without crashing your program.
Introduction
Exceptions occur when an operation cannot finish, such as converting invalid input to an integer.
Use try for risky code, except for recovery, and finally for cleanup that must always happen.
Key insight
Handle errors without crashing your program.
Example
try:
number = int("not a number")
except ValueError:
print("Please enter digits")This example shows the core exceptions idea in a small, runnable program.
Real-world example
Forms use exception handling to show useful validation messages.
Test yourself
2-question check
1
What is the main idea in Exceptions?
2
Where can exceptions be useful?
Ready to check your understanding?
Answer every question, then submit your quiz.
Try it yourself
Python compiler
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Output appears here
First run downloads the Python runtime, so it may take a moment.
Practice challenge
Catch a ZeroDivisionError when dividing two numbers.