The code below adds Sensei support to your Divi Theme. To use it simply copy it to your Divi functions.php file.

functions.php

/**
 * Declare Sensei support
 *
 * This is needed to hide the Sensei theme compatibility notice your admin dashboard.
 */
add_action( 'after_setup_theme', 'divi_sensei_support' );
function divi_sensei_support() {
	add_theme_support( 'sensei' );
}

/**
 * Remove the default Sensei wrappers
 */
global $woothemes_sensei;
remove_action( 'sensei_before_main_content', array( $woothemes_sensei->frontend, 'sensei_output_content_wrapper' ), 10 );
remove_action( 'sensei_after_main_content', array( $woothemes_sensei->frontend, 'sensei_output_content_wrapper_end' ), 10 );

/**
 * Add Divi specific custom  Sensei content  wrappers
 */
add_action('sensei_before_main_content', 'divi_sensei_wrapper_start', 10);
add_action('sensei_after_main_content', 'divi_sensei_wrapper_end', 10);

function divi_sensei_wrapper_start() {
	echo '<div id="main-content">
			<div class="container">
				<div id="content-area" class="clearfix">
					<div id="left-area">';
		//<div id="content-area" class="clearfix">'
	//echo '<div id="primary" class="content-area"><main id="main" class="site-main" role="main">';
}

function divi_sensei_wrapper_end() {
	echo '			</div> <!-- #left-area -->';
	get_sidebar();
	echo '     </div> <!-- #content-area -->
			</div> <!-- div.container -->
        </div><!-- #main-content -->';
}