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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 Convert(self, metadata, stat_entry, token=None):
 """Converts StatEntry to ExportedRegistryKey. Does nothing if StatEntry corresponds to a file and not a registry entry. Args: metadata: ExportedMetadata to be used for conversion. stat_entry: StatEntry to be converted. token: Security token. Returns: List or generator with resulting RDFValues. Empty list if StatEntry corresponds to a file and not to a registry entry. """

    if stat_entry.pathspec.pathtype != rdf_paths.PathSpec.PathType.REGISTRY:
      return []

    result = ExportedRegistryKey(
        metadata=metadata,
        urn=stat_entry.AFF4Path(metadata.client_urn),
        last_modified=stat_entry.st_mtime)

    if (stat_entry.HasField("registry_type") and
        stat_entry.HasField("registry_data")):

      result.type = stat_entry.registry_type

      # `data` can be value of arbitrary type and we need to return `bytes`. So,
      # if it is `bytes` we just pass it through. If it is not, we stringify it
      # to some human-readable form and turn it to `bytes` by UTF-8 encoding.
      data = stat_entry.registry_data.GetValue()
      if isinstance(data, bytes):
        result.data = data
      else:
        result.data = str(data).encode("utf-8")

    return [result]