difference between __repr__() and __str__()

[Fredrik Lundh]

Gregoire Welraeds wrote:
> __repr__: called to compute the official string representation of an
> object. This should like a valid Python expression that can be used to
> recreate an object with the same value.
>
> __str__: differs from repr in that in does not have to be a valid python
> expression: a more conveniant or concise representation maybe used
> instead.

according to the eff-bot:

    __repr__ should something that makes sense to a
    programmer, but not necessarily to someone else.
    (think "debugging")

    (e.g. basic types return a string literal, more complex
    types usually return some kind of descriptor, such as
    "<foo instance at 912388>" or "<open file 'foo', mode
    'r' at 918747>")

    __str__ should be used to convert the contents of an
    object to a (usually printable) string, whenever that
    makes sense (think "class design")

</F>