Meta Slider - Flex Slider - Move carousel 1 image at a time

/**
 * INSTALLATION: this code should be pasted into your theme's functions.php file.
 *
 * Compatibility: Flex Slider.
 */
function metaslider_flex_carousel_move($options, $slider_id, $settings) {
    $options['move'] = 1;
    return $options;
}
add_filter('metaslider_flex_slider_parameters', 'metaslider_flex_carousel_move', 11, 3);

I've been trying to get this solution to work. And it doesn't, unfortunately.
Firstly, in line seven, the " after 1 shows up as a syntax error.
Secondly, are you sure about putting this into the theme's functions.php file? I'd have thought it should be put somewhere within the actual Meta Slider plugin. But then, I am very new at this, so... :/

It works pretty fine, Thank you!

Thank you, this worked perfectly and flawlessly for me.

Thank you! Awesome! Still works great in 2019 :))