Disable use of pyc file with no matching py file

[Roy Smith]

Every so often (typically when refactoring), I'll remove a .py file and forget to remove the corresponding .pyc file.  If I then import the module, python finds the orphaned .pyc and happily imports it.  Usually leading to confusing and hard to debug failures.

Is there some way to globally tell python, "Never import a .pyc unless the corresponding .py file exits"?  Perhaps some environment variable I could set in my .login file?