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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 get_rest_token(self):
 """ Returns an auth token for making calls to eventhub REST API. :rtype: str """

        uri = urllib.parse.quote_plus(
            "https://{}.{}/{}".format(self.sb_name, self.namespace_suffix, self.eh_name))
        sas = self.sas_key.encode('utf-8')
        expiry = str(int(time.time() + 10000))
        string_to_sign = ('{}\n{}'.format(uri, expiry)).encode('utf-8')
        signed_hmac_sha256 = hmac.HMAC(sas, string_to_sign, hashlib.sha256)
        signature = urllib.parse.quote(base64.b64encode(signed_hmac_sha256.digest()))
        return 'SharedAccessSignature sr={}&sig={}&se={}&skn={}' \
                .format(uri, signature, expiry, self.policy)