common code, def a function vs exec() a string

[Skaperen]

i do use exec() to process config files. that lets me put dynamic code in the config file from simple things like:

howmanytimes = 2**32

to more complex code that figures out config parameters based on other information sources. it gets the local namespace back from exec() and deletes key '__builtins__' from that dictionary. it then hangs on to that dictionary for config settings or sets up things, sooner, such as opening files.