code: func (s *fs) Open(name string) (http.File, error) {
  	fi, ok := s.m[name]
  	if !ok {
  		return nil, os.ErrNotExist
  	}
  	return &file{fileInfo: fi}, nil
  }
docs: // Open is called with names like "/goog/base.js", but the zip contains Files named like "closure/goog/base.js".