Python Exception Handling Explained for Beginners

Python Exception Handling Explained (try, except, finally)

Introduction

In the previous post, we learned about Python File Handling. Now let's learn how to handle errors so our program does not crash.

This is called Exception Handling.

Errors happen in real programs. A good programmer knows how to handle them properly.

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What is an Exception?

An exception is an error that occurs during program execution.

print(10 / 0)

This causes an error because division by zero is not allowed.

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Why Use Exception Handling?

• Prevents program from crashing
• Makes code more stable
• Helps handle user mistakes
• Used in real-world applications

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Using try and except

We use try to test code and except to handle the error.

try:
    num = int(input("Enter a number: "))
    print(10 / num)
except:
    print("Error occurred!")

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Handling Specific Errors

We can handle specific types of exceptions.

try:
    num = int(input("Enter number: "))
    print(10 / num)

except ValueError:
    print("Invalid input!")

except ZeroDivisionError:
    print("Cannot divide by zero!")

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Using finally

The finally block always runs whether an error occurs or not.

try:
    f = open("data.txt")
    print(f.read())

except:
    print("File not found!")

finally:
    print("Execution finished.")

finally is commonly used to close files or release resources.

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Using else Block

The else block runs only if no error occurs.

try:
    num = int(input("Enter number: "))
except:
    print("Error!")

else:
    print("You entered:", num)

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Real-Life Example

try:
    age = int(input("Enter your age: "))
    print("Age saved successfully.")

except:
    print("Please enter a valid number!")

This prevents the program from crashing if the user enters text.

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What You Learned in This Post

• What is an exception
• Using try and except
• Handling specific errors
• Using finally and else
• Writing safe programs

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What’s Next?

Now that you can handle errors, we will move to an important concept used in real projects:

Next Post: Python Modules and Import Statement Explained

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About the Author

Ayush Gupta
MSc AI/ML Student | Python & Machine Learning Enthusiast