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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 authenticate(self, transport, account_name, password=None):
 """ Authenticates account using soap method. """

        Authenticator.authenticate(self, transport, account_name, password)

        if password == None:
            return self.pre_auth(transport, account_name)
        else:
            return self.auth(transport, account_name, password)