Source

File: wp-admin/includes/class-wp-list-table.php

public function get_pagenum() {
		$pagenum = isset( $_REQUEST['paged'] ) ? absint( $_REQUEST['paged'] ) : 0;

		if ( isset( $this->_pagination_args['total_pages'] ) && $pagenum > $this->_pagination_args['total_pages'] ) {
			$pagenum = $this->_pagination_args['total_pages'];
		}

		return max( 1, $pagenum );
	}