Option	Type	Valid For ‘Filtertype’ Of	Description
function	function	[‘function’]	The handle for a callable Python object (e.g. function) that should be used to determine if a message should be filtered or a string of the form “<function file>:<function name>” identifying a function where “<function file>” is the module or Python file containing the function and “<function name>” is the name of the function. The function should take the message as input and return a boolean, True if the message should pass through the filter, False if it should not.
statement	string	[‘statement’]	Python statement in terms of the message as represented by the string “%x%” that should evaluate to a boolean, True if the message should pass through the filter, False if it should not. The statement should only use a limited set of builtins and the math library (See yggdrasil.tools.safe_eval). If more complex relationships are required, use the FunctionFilter class.