docs: def get_source(self, name):
          """Concrete implementation of InspectLoader.get_source."""
          path = self.get_filename(name)
          try:
              source_bytes = self.get_data(path)
          except OSError as exc:
              e = _ImportError('source not available through get_data()',
                               name=name)
              e.__cause__ = exc
              raise e
          return decode_source(source_bytes)