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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 _compress_json(self, j):
 """Compress the BLOB data portion of the usernotes. Arguments: j: the JSON in Schema v5 format (dict) Returns a dict with the 'users' key removed and 'blob' key added """

        compressed_json = copy.copy(j)
        compressed_json.pop('users', None)

        compressed_data = zlib.compress(
            json.dumps(j['users']).encode('utf-8'),
            self.zlib_compression_strength
        )
        b64_data = base64.b64encode(compressed_data).decode('utf-8')

        compressed_json['blob'] = b64_data

        return compressed_json