Login wp admin without password in one file (localhost)

login.php

<?php

require __DIR__ . '/wp-load.php';

$username = 'admin';
$user = get_user_by('login', $username );

// Redirect URL //
if ( !is_wp_error( $user ) )
{
    wp_clear_auth_cookie();
    wp_set_current_user ( $user->ID );
    wp_set_auth_cookie  ( $user->ID );

    $redirect_to = user_admin_url();
    wp_safe_redirect( $redirect_to );
    exit();
}