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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 _ReadLabels(self, artifact_definition_values, artifact_definition, name):
 """Reads the optional artifact definition labels. Args: artifact_definition_values (dict[str, object]):
 artifact definition values. artifact_definition (ArtifactDefinition):
 an artifact definition. name (str):
 name of the artifact definition. Raises: FormatError: if there are undefined labels. """

    labels = artifact_definition_values.get('labels', [])

    undefined_labels = set(labels).difference(self.labels)
    if undefined_labels:
      raise errors.FormatError(
          'Artifact definition: {0:s} found undefined labels: {1:s}.'.format(
              name, ', '.join(undefined_labels)))

    artifact_definition.labels = labels