package Foo;

use strict;
use warnings;

my %defaults =
(
    -foo => "foo",
    -bar => "bar",
);

sub import
{
    shift;
    my %def = @_;
    $defaults{$_} = $def{$_} for keys %def;
}

sub new
{
    my $class = shift;
    my $number = shift;
    my %args = @_;

    # BEGIN QUESTION
    my %realargs = ();

    for ( keys %args )
    {
        my $value = $args{$_};

        $_ = lc($_); s/^(?!-)/-/;

        $realargs{$_} = $value;
    }

    for ( keys %defaults )
    {
        my $value = $defaults{$_};

        $_ = lc($_);
        s/^(?!-)/-/;

        $realargs{$_} = $value unless exists $realargs{$_};
    }
    
    # BEGIN QUESTION

    my $self = bless {}, $class;

    return $self;
}
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