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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 shard_filename(path, tag, shard_num, total_shards):
 """Create filename for data shard."""

  return os.path.join(
      path, "%s-%s-%s-%.5d-of-%.5d" % (_PREFIX, _ENCODE_TAG, tag, shard_num, total_shards))