• Be me.
• Apply for job listing that requires Python experience.
• /home/tootsweet/python_projects/python_genius.py
• Called and invited to team interview.
• Arrive dressed like perfect corporate cog, leather binder in hand.
• "Do you know C#?"
• Listing never mentioned C#.
• Me: "No."
• "We're switching from Python to C#."
• Didn't get the job.

Later worked with former employees of $aforementioned_employer. They have a terrible habit of hiring in droves, only to lay off half their workforce every few years.