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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 generate_identity(self):
 """ Generate a unique but random identity. """

        identity = struct.pack('!BI', 0, self._base_identity)
        self._base_identity += 1

        if self._base_identity >= 2 ** 32:
            self._base_identity = 0

        return identity