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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 _read_json_file(self):
 """ read metadata from a json file. :return: the parsed json dict :rtype: dict """

        with open(self.json_uri) as metadata_file:
            try:
                metadata = json.load(metadata_file)
                return metadata
            except ValueError:
                message = tr('the file %s does not appear to be valid JSON')
                message = message % self.json_uri
                raise MetadataReadError(message)