Python license (2.3)

[Robert Kern]

Antoon Pardon wrote:
> Op 2005-04-13, Robert Kern schreef <rkern at ucsd.edu>:
> 
>>Antoon Pardon wrote:
>>
>>>Op 2005-04-13, Robert Kern schreef <rkern at ucsd.edu>:
>>
>>>>Yes, the license text and the copyright notice must be attached. It 
>>>>doesn't mean that the PSF license is the operative one for the 
>>>>derivative work.
>>>
>>>
>>>Why attach a license that is not operative. That doesn't make sense
>>>to me and will IMO just create confusion.
>>
>>Because it's not your code. The tiny obligation that you have to satisfy 
>>is to say that some of the code comes from someone else and is available 
>>under such-and-such a license. That's it. You can keep the code hidden, 
>>you can charge whatever you like for it, but you have to attribute it 
>>properly. Open source licenses don't get much less restrictive than this.
> 
> 
> Well maybe this is a semantic problem. I wouldn't use the word "attach"
> here.

Fair enough. The license text is included *for reference*, not because 
it is *the* license for the derived work. In fact, it *can't* be the 
license of the derived work because you are not the PSF.

> So what I seem obligated to do, is 1) Mentioning this came
> from the python distribution and 2) explain where this distribution can
> be attained and under what license.

The minimum is:

1) Put the copyright notice in.
2) Reference a copy of the PSF License. (Practically speaking, a URL 
will probably do.)
3) List the modifications you made.
4) Put your copyright notice in and whatever terms you want to apply.

>>Of course, IANAL and TINLA, so if you want real legal advice instead of 
>>advice from random newsgroup bums like myself, you should talk to a lawyer.
> 
> 
> Well if it comes so far I have to consult a lawyer I'd rather not publish
> it in the first place.

Then take the (free) advice that you asked for. And please do read 
Rosen's book.

> The only reason I'm concerned is that this is to be part of a tutorial
> and I prefer not to burden those who read the tutoral with any kind of
> license. As far as I'm concerned people reading the tutorial can use
> any code provided with it in any way they see fit.

You can't *quite* go that far if you are deriving code from Python, but 
it's about as close as you can get. You still have those light 
restrictions about attribution and notification of changes.

> I see this as my contribution to the communities who has provided me
> with all kinds of things that are usefull to me. I'm willing to put
> time into this, but if I have to spend money because it is impossible
> otherwise to find out how to contribute legally, that is a hurdle
> I'm reluctant to take.

You could take a look at what other people are doing. Most of us here 
are writing and releasing software derived from Python, legally so and 
without complication.

No one but your own lawyer can make any guarantees, but most of us here 
have done just fine without one.

-- 
Robert Kern
rkern at ucsd.edu

"In the fields of hell where the grass grows high
  Are the graves of dreams allowed to die."
   -- Richard Harter