What's wrong with the example in the Expect POD?

$exp->expect($timeout,
              [ qr/username: /i, sub { my $self = shift;
                                       $self->send("$username\r");
                                       exp_continue; }],
              [ qr/password: /i, sub { my $self = shift;
                                       $self->send("$password\r");
                                       exp_continue; }],
              $shell_prompt);
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All you need to add before it is something like:

print "username: ";
my $username = <STDIN>;
print "password: ";
my $password = <STDIN>;
chomp $username;
chomp $password;
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I've never used Expect, but the POD seems pretty clear.