@staticmethod<EOL><INDENT>def register_handler(class_name, handler):<DEDENT>
SqlLoaderWriter.handlers[class_name] = handler<EOL>
Registers a handler for writing instances of a class as a field to the destination file.

:param str class_name: The name of the class.
:param callable handler: The handler. This handler will be called with two arguments: the object which value
                         must be writen to the destination file, the file handler.