Parses <EventWriter>

        @param node: Node containing the <EventWriter> element
        @type node: xml.etree.Element

def parse_event_writer(self, node):
        """
        Parses <EventWriter>

        @param node: Node containing the <EventWriter> element
        @type node: xml.etree.Element
        """

        if 'path' in node.lattrib:
            path = node.lattrib['path']
        else:
            self.raise_error('<EventWriter> must specify a path.')

        if 'filename' in node.lattrib:
            file_path = node.lattrib['filename']
        else:
            self.raise_error("Event writer for '{0}' must specify a filename.",
                             path)
                             
        if 'format' in node.lattrib:
            format = node.lattrib['format']
        else:
            self.raise_error("Event writer for '{0}' must specify a format.",
                             path)

        self.current_simulation.add_event_writer(EventWriter(path, file_path, format))