function external_images($url_external = null)

function external_images($url_external = null)
    {

		// Gives us access to the download_url() and wp_handle_sideload() functions
		require_once( ABSPATH . 'wp-admin/includes/file.php' );
		// URL to the WordPress logo
		$url = $url_external;
		$timeout_seconds = 5;
		
		// Download file to temp dir
		$temp_file = download_url( $url, $timeout_seconds );
		
		if ( !is_wp_error( $temp_file ) ) {
			// Array based on $_FILE as seen in PHP file uploads
			$file = array(
				'name'     => basename($url), // ex: wp-header-logo.png
				'type'     => 'image/png',
				'tmp_name' => $temp_file,
				'error'    => 0,
				'size'     => filesize($temp_file),
			);
			$overrides = array(
				// Tells WordPress to not look for the POST form
				// fields that would normally be present as
				// we downloaded the file from a remote server, so there
				// will be no form fields
				// Default is true
				'test_form' => false,
				// Setting this to false lets WordPress allow empty files, not recommended
				// Default is true
				'test_size' => true,
			);
			// Move the temporary file into the uploads directory
			$results = wp_handle_sideload( $file, $overrides );
			if ( !empty( $results['error'] ) ) {
				// Insert any error handling here
			} else {
				
				$filename  = $results['file']; // Full path to the file
				$local_url = $results['url'];  // URL to the file in the uploads dir
				$type      = $results['type']; // MIME type of the file
				// Check the type of file. We'll use this as the 'post_mime_type'.
				$filetype = wp_check_filetype( basename( $filename ), null );

				// Get the path to the upload directory.
				$wp_upload_dir = wp_upload_dir();

				// Prepare an array of post data for the attachment.
				$attachment = array(
					'guid'           => $wp_upload_dir['url'] . '/' . basename( $filename ), 
					'post_mime_type' => $filetype['type'],
					'post_title'     => preg_replace( '/\.[^.]+$/', '', basename( $filename ) ),
					'post_content'   => '',
					'post_status'    => 'inherit'
				);

				//HOWTO: get the current created/updated post?
				$post_id = null;

				//if image exist update else create it
				if (post_exists(basename( $filename ))){
					$page = get_page_by_title(basename( $filename ), OBJECT, 'attachment');
					$attach_id = $page->ID;

					$attach_data = wp_generate_attachment_metadata( $attach_id, $filename ); // Generate attachment data, filesize, height, width etc.

					wp_update_attachment_metadata( $attach_id, $attach_data ); // Add the above meta data

					return $local_url;

				}
				else{
					// Insert the attachment.
					$attach_id = wp_insert_attachment( $attachment, $filename, $post_id );

					// Make sure that this file is included, as wp_generate_attachment_metadata() depends on it.
					require_once( ABSPATH . 'wp-admin/includes/image.php' );

					// Generate the metadata for the attachment, and update the database record.
					$attach_data = wp_generate_attachment_metadata( $attach_id, $filename );
					wp_update_attachment_metadata( $attach_id, $attach_data );

					set_post_thumbnail( $post_id, $attach_id );

					// Perform any actions here based in the above results
					return $local_url;
				}
			}
		}
	}