I just extracted the following line from the Python documentation (for those of you who don’t know, Python is a relatively-new and somewhat unusual programming language who’s name is derived not from the snake but from Monty Python):

Attempts to pickle unpicklable objects will raise the PicklingError exception; when this happens, an unspecified number of bytes may have already been written to the underlying file.

You have to love any manual with that line in it! It almost beats the famous Fortran line about defining pi as a constant in case it’s value changes.