Fix Python Syntax Error

I have a single Python file that refuses to run because of a syntax error. I need a fresh pair of eyes to locate the exact line that is breaking execution, correct it, and briefly explain what went wrong so I can avoid the same mistake next time.

Please work with standard Python 3.x; no third-party packages are involved. A quick turnaround is appreciated.

Deliverables:
• Repaired .py file that runs without errors
• Short note (one or two sentences) describing the original issue and the fix