Comment form customization

function my_update_comment_fields( $fields ) {

    $commenter = wp_get_current_commenter();
    $req       = get_option( 'require_name_email' );
    $label     = $req ? '*' : ' ' . __( '(optional)', 'text-domain' );
    $aria_req  = $req ? "aria-required='true'" : '';

    $fields['author'] =
        '<p class="comment-form-author">
            <label for="author">' . __( "Name", "text-domain" ) . $label . '</label>
            <input id="author" name="author" type="text" placeholder="' . esc_attr__( "Jane Doe", "text-domain" ) . '" value="' . esc_attr( $commenter['comment_author'] ) .
        '" size="30" ' . $aria_req . ' />
        </p>';

    $fields['email'] =
        '<p class="comment-form-email">
            <label for="email">' . __( "Email", "text-domain" ) . $label . '</label>
            <input id="email" name="email" type="email" placeholder="' . esc_attr__( "[email protected]", "text-domain" ) . '" value="' . esc_attr( $commenter['comment_author_email'] ) .
        '" size="30" ' . $aria_req . ' />
        </p>';

    $fields['url'] =
        '<p class="comment-form-url">
            <label for="url">' . __( "Website", "text-domain" ) . '</label>
            <input id="url" name="url" type="url"  placeholder="' . esc_attr__( "http://google.com", "text-domain" ) . '" value="' . esc_attr( $commenter['comment_author_url'] ) .
        '" size="30" />
            </p>';

    return $fields;
}
add_filter( 'comment_form_default_fields', 'my_update_comment_fields' );

// Comment field

function my_update_comment_field( $comment_field ) {

  $comment_field =
    '<p class="comment-form-comment">
            <label for="comment">' . __( "Comment", "text-domain" ) . '</label>
            <textarea required id="comment" name="comment" placeholder="' . esc_attr__( "Enter comment here...", "text-domain" ) . '" cols="45" rows="8" aria-required="true"></textarea>
        </p>';

  return $comment_field;
}
add_filter( 'comment_form_field_comment', 'my_update_comment_field' );