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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def AddFileWithUnknownHash(client_path, blob_refs, use_external_stores=True):
 """Add a new file consisting of given blob IDs."""

  precondition.AssertType(client_path, db.ClientPath)
  precondition.AssertIterableType(blob_refs, rdf_objects.BlobReference)
  return AddFilesWithUnknownHashes(
      {client_path: blob_refs},
      use_external_stores=use_external_stores)[client_path]