颜色选项主题定制器API无输出

I'm trying to get output from below setting but it is now working and displaying blank. When I try to echo in plan text then some times it appear in customizer mode. i'm using <?php echo get_theme_mod( 'shoplabel_color' ); ?> to Get output. Is there anything which i'm missing like javascript or any?

$wp_customize->add_setting('label_color',
        array(
            'default'           => '43AC6A',
            'type'              => 'theme_mod',
            'capability'        => 'edit_theme_options',
                       'sanitize_callback'  => 'theme_slug_sanitize_hex_color'
        ));


             $wp_customize->add_control(
                     new WP_Customize_Color_Control($wp_customize, 'label_color',
                     array (

                         'settings'     => 'label_color',
                         'section'      => 'my_theme_page',

        'label'         => __( 'Label color', 'theme_slug' )


                     )  ));

Ok resolve the issue problem in default function which i copied from chip code so now I write new function, It's working

function theme_slug_sanitize_hex_color( $color ) {
    if ( '' === $color )
        return '';

    // 3 or 6 hex digits, or the empty string.
    if ( preg_match('|^#([A-Fa-f0-9]{3}){1,2}$|', $color ) )
        return $color;

    return null;
}