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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 create_negotiate_message(self, domain_name=None, workstation=None):
 """ Create an NTLM NEGOTIATE_MESSAGE :param domain_name: The domain name of the user account we are authenticating with, default is None :param worksation: The workstation we are using to authenticate with, default is None :return: A base64 encoded string of the NEGOTIATE_MESSAGE """

        self.negotiate_message = NegotiateMessage(self.negotiate_flags, domain_name, workstation)

        return base64.b64encode(self.negotiate_message.get_data())