is there any principle when writing python function

[Roy Smith]

In article <mailman.489.1314483681.27778.python-list at python.org>,
 Emile van Sebille <emile at fenx.com> wrote:

> code that doesn't execute will need to be read to be understood, and 
> to be fixed so that it does run.

That is certainly true, but it's not the whole story.  Even code that 
works perfectly today will need to be modified in the future.  Business 
requirements change.  Your code will need to be ported to a new OS.  
You'll need to make it work for 64-bit.  Or i18n.  Or y2k (well, don't 
need to worry about that one any more).  Or with a different run-time 
library.  A new complier.  A different database.  Regulatory changes 
will impose new requirements  Or, your company will get bought and 
you'll need to interface with a whole new system.

Code is never done.  At least not until the project is dead.