Index: inc/template-functions.php
===================================================================
--- inc/template-functions.php	(revision 39901)
+++ inc/template-functions.php	(working copy)
@@ -62,6 +62,12 @@
 	$colors = twentyseventeen_sanitize_colorscheme( get_theme_mod( 'colorscheme', 'light' ) );
 	$classes[] = 'colors-' . $colors;
 
+	// Add class for two columns template
+	if ( is_page_template( 'two-columns.php' ) && is_active_sidebar( 'sidebar-1' ) ) {
+		$classes[] = 'has-sidebar';
+		$classes = array_diff( $classes, array( 'page-two-column' ) );
+	}
+
 	return $classes;
 }
 add_filter( 'body_class', 'twentyseventeen_body_classes' );
Index: two-columns.php
===================================================================
--- two-columns.php	(nonexistent)
+++ two-columns.php	(working copy)
@@ -0,0 +1,35 @@
+<?php
+/**
+ * Template Name: Two columns Template
+ */
+
+get_header(); ?>
+<div class="wrap">
+	<div id="primary" class="content-area">
+		<main id="main" class="site-main" role="main">
+
+			<?php
+				/* Start the Loop */
+				while ( have_posts() ) : the_post();
+
+					get_template_part( 'template-parts/post/content', get_post_format() );
+
+					// If comments are open or we have at least one comment, load up the comment template.
+					if ( comments_open() || get_comments_number() ) :
+						comments_template();
+					endif;
+
+					the_post_navigation( array(
+						'prev_text' => '<span class="screen-reader-text">' . __( 'Previous Post', 'twentyseventeen' ) . '</span><span aria-hidden="true" class="nav-subtitle">' . __( 'Previous', 'twentyseventeen' ) . '</span> <span class="nav-title"><span class="nav-title-icon-wrapper">' . twentyseventeen_get_svg( array( 'icon' => 'arrow-left' ) ) . '</span>%title</span>',
+						'next_text' => '<span class="screen-reader-text">' . __( 'Next Post', 'twentyseventeen' ) . '</span><span aria-hidden="true" class="nav-subtitle">' . __( 'Next', 'twentyseventeen' ) . '</span> <span class="nav-title">%title<span class="nav-title-icon-wrapper">' . twentyseventeen_get_svg( array( 'icon' => 'arrow-right' ) ) . '</span></span>',
+					) );
+
+				endwhile; // End of the loop.
+			?>
+
+		</main><!-- #main -->
+	</div><!-- #primary -->
+	<?php get_sidebar(); ?>
+</div><!-- .wrap -->
+
+<?php get_footer();