More random python observations from a perl programmer

[Roy Smith]

Arrrgh!  I should proofread more carefully before I post.

I wrote:

> Roof_material and roof_color are NOT orthogonal; while color can be white
> or green, it can only be so if material is not ceramic_tile.

Obviously, I meant white or blue.

> x = 4 + 3
> x = 4.0 + 3.0
> x = "Four" + "Three"
> 
> are legal, with x getting the value 4, 4.0, and "FourThree" respectively. 

Make that 7, 7.0, and "FourThree".  It's been a tough week, but I think I
should still be able to handle single-digit integer addition on my own :-(