Answered Importing users

<?php
    $groups = array();
    $groups['Group1']['usergroup'] = '7'; // id of group
    $groups['Group1']['role'] = '1'; // id of role
    $groups['Group2']['usergroup'] = '8';
    $groups['Group2']['role'] = '1';
    $fields = array();
    $fields['active'] = true;
    $fields['passwordgenmethod'] = 'g'; // automatically generate password
    $fields['passwordnotifymethod'] = 'e'; // email user his login details
    $fields['email'] = $email; 
    $fields['username'] = $username;
    $fields['fullname'] = $fullname;
    $fields['extended']['container']['name'] = $value;
    $fields['groups'] = $groups;
    $response = $modx->runProcessor('security/user/create', $fields);
  }