Get built-in function from the function name
<p>How can I get the int(), float(), dict(), etc. callables from their names?  For example, I'm trying to save Python values to xml and storing the variable type as a string.  Is there a way to get the callable from the string when converting from string back to the Python type?</p>

<p>Normally I would do something like getattr(myobj, 'str'), but there is no module to use as the first argument for these built-in conversion functions.  I've also tried getattr(object, 'str'), but this doesn't work either since these functions are not part of the base 'object' type, merely globals to the language.</p>
