code: def add_attendees(self, attendees, required=True):
      
  
      new_attendees = self._build_resource_dictionary(attendees, required=required)
  
      for email in new_attendees:
        self._attendees[email] = new_attendees[email]
  
      self._dirty_attributes.add(u'attendees')
docs: Adds new attendees to the event.
  
      *attendees* can be a list of email addresses or :class:`ExchangeEventAttendee` objects.