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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 encrypt_text(self, text, *args, **kwargs):
 """ Encrypt a string. input: unicode str, output: unicode str """

        b = text.encode("utf-8")
        token = self.encrypt(b, *args, **kwargs)
        return base64.b64encode(token).decode("utf-8")