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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 _GetExtractionErrorsAsWarnings(self):
 """Retrieves errors from from the store, and converts them to warnings. This method is for backwards compatibility with pre-20190309 storage format stores which used ExtractionError attribute containers. Yields: ExtractionWarning: extraction warnings. """

    for extraction_error in self._GetAttributeContainers(
        self._CONTAINER_TYPE_EXTRACTION_ERROR):
      error_attributes = extraction_error.CopyToDict()
      warning = warnings.ExtractionWarning()
      warning.CopyFromDict(error_attributes)
      yield warning