public CorpusZipWriter(string path, IDocumentDataSerializer <T> dataSerializer) : this(path, dataSerializer, new FileSystem())
 {
 }
 public CorpusZipWriter(string path, IDocumentDataSerializer <T> dataSerializer, IFileSystem fileSystem) : base(path, fileSystem)
 {
     this.dataSerializer = dataSerializer;
 }
 public CorpusZipReader(string path, IDocumentDataSerializer <T> dataSerializer, IFileSystem fileSystem) : base(path, fileSystem)
 {
     this.dataSerializer = dataSerializer;
     metadata            = ReadCorpusZipMetadata();
 }