anchor.diff:        ..addFlag('customers',
             abbr: 'c',
             defaultsTo: false,
  -          help: 'Only show issues with customer labels');
  +          help: 'Only show issues with customer labels')
  +      ..addOption('delta', abbr: 'd', help: 'delta between dates, default = 7');
  +
       try {
         _results = _parser.parse(args);
         if (_results['help']) _printUsage();
  
positive.code:   return count;
  }
  
  Duration meanDurationWithOrWithoutCustomers(List<dynamic> issues,
      {bool onlyCustomers}) {
    double sum = 0.0;
    var count = issues == null ? 0 : issues.length;
    if (count == 0) return Duration(seconds: 0);
    bool hasCustomer = false;
    for (var item in issues) {
      var issue = item as Issue;
      if (issue.closedAt == null) continue;
      if (onlyCustomers)
        for (var label in issue.labels.labels) {
          if (label.label.contains('customer:')) {
            hasCustomer = true;
            break;
          }
        }
      if (!onlyCustomers || (onlyCustomers && hasCustomer)) {
        var delta = issue.closedAt.difference(issue.createdAt);
        sum += delta.inSeconds;
      }
    }
    if (count == 0)
      return Duration(seconds: 0);
    else {
      int sumAsInt = sum.toInt();
      int mean = sumAsInt ~/ count;
      return Duration(seconds: mean);
    }
  }
  
  
negative.code:   bool get summarize => _results['summarize'];
    bool get showQueries => _results['queries'];
    bool get onlyCustomers => _results['customers'];
    int get deltaDays =>
        int.parse(_results['delta'] == null ? '7' : _results['delta']);
    int get exitCode => _results == null
        ? -1
        : _results['help']
  