def delete_user(username, uid=None):
    '''
    Delete a user

    CLI Example:

    .. code-block:: bash

        salt dell drac.delete_user [USERNAME] [UID - optional]
        salt dell drac.delete_user diana 4
    '''
    if uid is None:
        user = list_users()
        uid = user[username]['index']

    if uid:
        return __execute_cmd('config -g cfgUserAdmin -o \
                              cfgUserAdminUserName -i {0} ""'.format(uid))

    else:
        log.warning('\'%s\' does not exist', username)
        return False

    return True