Challenge 1: A Basic Class — Possible Solution
====================================================================

package Book;

sub new {
    my $class = shift;
    my $title = shift;
    my $self = { title => $title };
    return bless $self, $class;
}

sub describe {
    my $self = shift;
    return "Title: $self->{title}";
}

package main;
use strict;
use warnings;
use feature 'say';

my $book = Book->new("Perl Fundamentals");
say $book->describe();

Output:
Title: Perl Fundamentals

WHY THIS WORKS AS AN ANSWER
------------------------------
package Book; reuses the chapter's own namespace-declaration syntax
exactly, establishing where the following subroutines belong.

sub new reuses the chapter's own constructor pattern precisely: shift
the class name off @_ first (Book, per the challenge's own warn-box
about getting this order right), shift the title next, build an
ordinary anonymous hashref (Course 1, Chapter 9) storing it under a
title key, and bless that hashref into the given class before
returning it.

sub describe reuses the chapter's own method pattern — my $self =
shift; as the first line to unpack the invocant, then an
interpolated string (Course 1, Chapter 2) pulling $self->{title}
back out via the chapter's own arrow-dereference syntax, matching
exactly the format the challenge requests.

Book->new("Perl Fundamentals") reuses the chapter's own $obj->new(...)
call-syntax explanation directly — this is sugar for new(Book,
"Perl Fundamentals"), which is why $class correctly receives "Book"
and $title correctly receives "Perl Fundamentals" inside new, in that
order.