docs: function recorder(opts, fn) {
    var group = stack[stack.length - 1];
    var response = null;
  
    assert(group, 'please specify copycat group');
    recordings = load(group) || [];
  
    recordings.forEach(function(recording) {
      if (!deepEqual(recording.opts, opts)) return;
      response = recording;
    });
  
    if (response) {
      return fn(response.err, response.res, response.body);
    }
  
    request(opts, function(err, res, body) {
      requests = requests || [];
      requests.push({ opts: opts, err: err, res: res, body: body });
      fn.apply(null, arguments);
    });
  }