code: public static IEntityGroup findGroup(String key) throws GroupsException {
          LOGGER.trace("Invoking findGroup for key='{}'", key);
          return instance().ifindGroup(key);
      }
docs: Returns a pre-existing <code>IEntityGroup</code> or null if the <code>IGroupMember</code>
  does not exist.
  
  @param key String - the group key.
  @return org.apereo.portal.groups.IEntityGroup