11. Error Handling

EAFP (Easier to Ask for Forgiveness than Permission)

Pythonic code prefers try/except over checking conditions.

Non-Pythonic:

python
if os.path.exists("file.txt"):
    open("file.txt")

Pythonic:

python
try:
    open("file.txt")
except FileNotFoundError:
    print("Missing file")

Why? Because between the check and the open, the file could disappear (Race Condition).

The finally Block

Always runs. Used for cleanup (closing files, DB connections).