Level's are specified as simple text files, with numerous assumtpions

The file layout is

Level name
Tileset name
Map data as a grid of ascii characters
"end"
Advanced sprite definitions

Advanced sprite definitions consist of:

  (<x>, <y>): <SpriteClassName> <id> <arg1> <arg2>

<x> and <y> give the starting tile position.
<SpriteClassName> is looked up in mamba.sprites.
<id> is a means for other sprites to lookup the sprite.
<arg1> .. <argN> are string arguments to the sprite constructor.