def _parse_group(self, element):
self._log.debug('<STR_LIT>'.format(group=element.text))<EOL>if isinstance(self.groups, set):<EOL><INDENT>self.groups.add(element.text)<EOL><DEDENT>elif self.groups is None:<EOL><INDENT>self.groups = {element.text}<EOL><DEDENT>else:<EOL><INDENT>raise TypeError('<STR_LIT>'<EOL>.format(type=type(self.groups), groups=str(self.groups)))<EOL><DEDENT>
Parse and add a group requirement for this trigger
:param element: The XML Element object
:type  element: etree._Element