> Please watch the tone. It is borderline abusive and dismissive.

I apologize for the adverse impact there.  I will be more careful.

> Also, my expectation for Fraction("0.0015") would be to give Fraction(3, 2000), the same as would be given by Fraction(Decimal("0.0015")).

Yes, 0.0015 would be 3/2000.  However, in my example "0.0015" is the right endpoint of [0.0005, 0.0015), not the value "0.001" that we are seeking the fraction for.

> Perhaps this tracker issue should be closed and moved to python-ideas.  The notions are currently too immature to warrant more core developer time.

You have more experience with this than I.  I defer to you.

> Agreed. It seems that what Lee wants is some kind of blend between the simplest fraction and the closest fraction, and it's not clear exactly how that blend would work.

Drat.  I gave the code example in order to make that clear.  I guess we can continue to discuss this at "python-ideas".  My quick web search for that turns up a lot of things.  If you could give me a lead -- is there a web URL for that, is it an e-mail list, etc.?

Thank you all for your valuable comments.