def METHOD_NAME(self, length, factor=1):
    """Create attribute and populate group item
    length: number of subgroups to create
    factor: scale factor to use setting int value
    return: group_item
    """
    defn = self.att_resource.findDefinition('Test1')
    att = self.att_resource.createAttribute('Test1', defn)
    group_item = att.findGroup('Group1')
    for i in range(length):
        group_item.appendGroup()
        int_item = group_item.item(i, 0)
        int_item.setValue(i * factor)
        string_item = group_item.item(i, 1)
        string_item.setValue('s{}'.format(i))
    return group_item