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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 make_token(cls, ephemeral_token: 'RedisEphemeralTokens') -> str: """ Returns a token to be used x number of times to allow a user account to access certain resource. """

        value = ephemeral_token.key
        if ephemeral_token.scope:
            value += ''.join(ephemeral_token.scope)

        return get_hmac(cls.KEY_SALT + ephemeral_token.salt, value)[::2]