wordpress core file says error template.php

Above error code is here

I can not edit post page right now!!! Edit Post Page Screen is ALL white.

/**
 * Retrieves an array of post states from a post.
 *
 * @since 5.3.0
 *
 * @param WP_Post $post The post to retrieve states for.
 * @return string[] Array of post state labels keyed by their state.
 */
function get_post_states( $post ) {
	$post_states = array();

	if ( isset( $_REQUEST['post_status'] ) ) {
		$post_status = $_REQUEST['post_status'];
	} else {
		$post_status = '';
	}

	if ( ! empty( $post->post_password ) ) {
		$post_states['protected'] = _x( 'Password protected', 'post status' );
	}

	if ( 'private' === $post->post_status && 'private' !== $post_status ) {
		$post_states['private'] = _x( 'Private', 'post status' );
	}

	if ( 'draft' === $post->post_status ) {
		if ( get_post_meta( $post->ID, '_customize_changeset_uuid', true ) ) {
			$post_states[] = __( 'Customization Draft' );
		} elseif ( 'draft' !== $post_status ) {
			$post_states['draft'] = _x( 'Draft', 'post status' );
		}
	} elseif ( 'trash' === $post->post_status && get_post_meta( $post->ID, '_customize_changeset_uuid', true ) ) {
		$post_states[] = _x( 'Customization Draft', 'post status' );
	}

	if ( 'pending' === $post->post_status && 'pending' !== $post_status ) {
		$post_states['pending'] = _x( 'Pending', 'post status' );
	}

	if ( is_sticky( $post->ID ) ) {
		$post_states['sticky'] = _x( 'Sticky', 'post status' );
	}

	if ( 'future' === $post->post_status ) {
		$post_states['scheduled'] = _x( 'Scheduled', 'post status' );
	}

	if ( 'page' === get_option( 'show_on_front' ) ) {
		if ( (int) get_option( 'page_on_front' ) === $post->ID ) {
			$post_states['page_on_front'] = _x( 'Front Page', 'page label' );
		}

		if ( (int) get_option( 'page_for_posts' ) === $post->ID ) {
			$post_states['page_for_posts'] = _x( 'Posts Page', 'page label' );
		}
	}

	if ( (int) get_option( 'wp_page_for_privacy_policy' ) === $post->ID ) {
		$post_states['page_for_privacy_policy'] = _x( 'Privacy Policy Page', 'page label' );
	}
Trying to get property 'post_status' of non-object　

• This reply was modified 2 years, 5 months ago by kazskater99.
• This reply was modified 2 years, 5 months ago by kazskater99.

I just backed up date so i can edit post　no white page come up.

but still template error shown hopefully wait for proper wordpress version