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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 metadata(self):
 """ Retrieve the metadata info for this prefix Returns: dict: metadata info """

        if self._metadata is None:
            try:
                with open(self.paths.metadata()) as metadata_fd:
                    self._metadata = json.load(metadata_fd)
            except IOError:
                self._metadata = {}
        return self._metadata