ABCs of numbers
The numbers package provides a tower of numeric types that are all implementations of numbers.Number. Additionally, the fractions and decimal modules provide extension numeric types: fractions.Fraction and decimal.Decimal.
These definitions roughly parallel the mathematical thought on the various classes of numbers. An article available at http://en.wikipedia.org/wiki/Number_theory covers the basics of different kinds of numbers.
What's important is the question of how well computers implement mathematical abstractions. To be more specific, we want to be sure that anything that is computable in the abstract world of mathematics can be computed using a concrete computer. This is why the question of computability is so important. The idea behind a "Turing Complete" programming language is that it can compute anything that's computable by an abstract Turing Machine. A helpful article can be found at http://en.wikipedia.org/wiki/Computability_theory.
Python defines the following...
