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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 fromMessage(cls, message):
 """Generate a ServerError instance, extracting the error text and the error code from the message."""

        error_text = message.getArg(
            OPENID_NS, 'error', '<no error message supplied>')
        error_code = message.getArg(OPENID_NS, 'error_code')
        return cls(error_text, error_code, message)