function lmm_is_plugin_active($plugin)
{
    $active_plugins = get_option('active_plugins');
    $active_plugins = array_flip($active_plugins);
    if (isset($active_plugins[$plugin]) || lmm_is_plugin_active_for_network($plugin)) {
        return true;
    }
}
function lmm_is_plugin_active($plugin)
{
    return in_array($plugin, (array) get_option('active_plugins', array())) || lmm_is_plugin_active_for_network($plugin);
}