my $self = shift;
  my $filename = shift;

  my $net = Clair::Network->new(directed => 1);

  open(FIN, $filename) or die "Couldn't open $filename: $!\n";

  my $in_vertices = 0;
  my $in_edges = 0;
  my $in_arcs = 0;
  while (<FIN>) {
    if (/\*Vertices/i) {
      $in_vertices = 1;
    } elsif (/\*Edges/i) {
      $in_edges = 1;
      $in_arcs = 0;
      $in_vertices = 0;
    } elsif (/\*Arcs/i) {
      $in_arcs = 1;
      $in_edges = 0;
      $in_vertices = 0;
    } else {
      chomp;
      $_ =~ s/^\s+//;
      if ($in_vertices) {
        my @v = split (/\s+/, $_);
        if (defined $v[1]) {
          $v[1] =~ s/\"//g;
          $net->add_node($v[0], $v[1]);
        } else {
          $net->add_node($v[0]);
        }
      } elsif ($in_arcs) {
        # directed edge
        my @e = split (/\s+/, $_);
        $net->add_edge($e[0], $e[1]);
      } elsif ($in_edges) {
        # undirected edge
        my @e = split (/\s+/, $_);
        $net->add_edge($e[0], $e[1]);
        $net->add_edge($e[1], $e[0]);
      }
    }
  }
  close FIN;

  return $net;