code: def append(self, v):
          '''
          >>> d = DiskVarArray('/tmp/test3', dtype='uint32')
          >>> d.append([1, 2, 3, 4])
          >>> d.__getitem__(0)
          memmap([1, 2, 3, 4], dtype=uint32)
          >>> d.append([5, 6, 7, 8])
          >>> d.__getitem__(1)
          memmap([5, 6, 7, 8], dtype=uint32)
          >>> shutil.rmtree('/tmp/test3', ignore_errors=True)
          '''
          self.index.append(len(self.data))
          self.data.extend(vf append(self, v):
          '''
          >>> d = DiskVarArray('/tmp/test3', dtype='uint32')
          >>> d.append([1, 2, 3, 4])
          >>> d.__getitem__(0)
          memmap([1, 2, 3, 4], dtype=uint32)
          >>> d.append([5, 6, 7, 8])
          >>> d.__getitem__(1)
          memmap([5, 6, 7, 8], dtype=uint32)
          >>> shutil.rmtree('/tmp/test3', ignore_errors=True)
          '''
          self.index.append(len(self.data))
          self.data.extend(v)
docs: >>> d = DiskVarArray('/tmp/test3', dtype='uint32')
          >>> d.append([1, 2, 3, 4])
          >>> d.__getitem__(0)
          memmap([1, 2, 3, 4], dtype=uint32)
          >>> d.append([5, 6, 7, 8])
          >>> d.__getitem__(1)
          memmap([5, 6, 7, 8], dtype=uint32)
          >>> shutil.rmtree('/tmp/test3', ignore_errors=True)