code: def OpenFile(client_path, max_timestamp=None):
    
  
    path_info = data_store.REL_DB.ReadLatestPathInfosWithHashBlobReferences(
        [client_path], max_timestamp=max_timestamp)[client_path]
  
    if path_info is None:
      raise FileHasNoContentError(client_path)
  
    hash_id = rdf_objects.SHA256HashID.FromBytes(
        path_info.hash_entry.sha256.AsBytes())
    blob_references = data_store.REL_DB.ReadHashBlobReferences([hash_id])[hash_id]
  
    if blob_references is None:
      raise MissingBlobReferencesError(
          "File hash was expected to have corresponding "
          "blob references, but they were not found: %r" % hash_id)
  
    return BlobStream(client_path, blob_references, hash_id)
docs: Opens latest content of a given file for reading.
  
    Args:
      client_path: A db.ClientPath object describing path to a file.
      max_timestamp: If specified, will open the last collected version with a
        timestamp equal or lower than max_timestamp. If not specified, will simply
        open the latest version.
  
    Returns:
      A file like object with random access support.
  
    Raises:
      FileHasNoContentError: if the file was never collected.
      MissingBlobReferencesError: if one of the blobs was not found.