{
  my %is_imported;

  sub lazy_use {
    my ($class, @args) = @_;
    unless ($is_imported{"$class @args"}++) {
      my $file = $class;
      $file =~ s-::-/-g;
      $file .= ".pm";
      require $file;

      my $importer = UNIVERSAL::can($class, "import");
      goto &$importer if defined $importer;
    }
  }
}