*Error Handling in Python*

When something unexpected happens — like dividing by zero or reading a missing file — Python raises an exception.
If not handled, your program crashes.


*The try...except Block*

try:
risky code
except SomeError:
handle error

*Example* :

try:
x = int(input(Enter a number: ))
print(10 / x)
except ZeroDivisionError:
print(You can't divide by zero!)
except ValueError:
print(Please enter a valid number.)


*else and finally*

else: runs if no exception was raised

finally: runs no matter what (cleanup code)


try:
num = int(input(Enter number: ))
except ValueError:
print(Not a number!)
else:
print(Square is, num ** 2)
finally:
print(Done.)


*Common Exceptions:*

- ZeroDivisionError – dividing by zero

- ValueError – invalid value (e.g., int(abc))

- TypeError – wrong data type

- FileNotFoundError – file doesn't exist

- IndexError – index out of range


*Mini Project: Safe Input Reader*

A safe input reader is a function or piece of code that asks the user for input — but doesn’t crash if the user types something invalid.

*Python Code*:

def get_integer(prompt):
try:
return int(input(prompt))
except ValueError:
print(That's not a valid integer!)
return None

num = None
while num is None:
num = get_integer(Enter an integer: )

print(You entered:, num)


*This project helps:*

- Prevent program crashes

- Give user-friendly error messages

- Build real-world safety into your code