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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, account_name, password):
 """ Authenticates zimbra account. @param account_name: account email address @param password: account password @raise AuthException: if authentication fails @raise SoapException: if soap communication fails """

        self.auth_token = self.authenticator.authenticate(self.transport,
                                                          account_name,
                                                          password)