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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 pack_init(self, recv, aud):
 """ Gather initial information for the payload. :return: A dictionary with claims and values """

        argv = {'iss': self.iss, 'iat': utc_time_sans_frac()}
        if self.lifetime:
            argv['exp'] = argv['iat'] + self.lifetime

        _aud = self.put_together_aud(recv, aud)
        if _aud:
            argv['aud'] = _aud

        return argv