public function is_enrolled( $product_ids = null, $relation = 'all', $use_cache = true ) {

		// Assume enrollment unless we find otherwise.
		$ret = true;

		// Allow a single product ID to be submitted (backwards compat).
		$product_ids = ! is_array( $product_ids ) ? array( $product_ids ) : $product_ids;

		foreach ( $product_ids as $id ) {

			$enrolled = ( 'enrolled' === strtolower( $this->get_enrollment_status( $id, $use_cache ) ) );

			// If use must be enrolled in all products and one is not enrolled: quit the loop & return false.
			if ( 'all' === $relation && ! $enrolled ) {
				$ret = false;
				break;

				// If user must be enrolled in any.
			} elseif ( 'any' === $relation ) {

				// If we find an enrollment: return true and quit the loop.
				if ( $enrolled ) {
					$ret = true;
					break;

					// If not switch return to false but keep looking.
				} else {
					$ret = false;
				}
			}
		}

		return apply_filters( 'llms_is_user_enrolled', $ret, $this, $product_ids, $relation, $use_cache );

	}