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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 set_lastmodified_date(self, date=None):
 """ Set the last modified date of a IOC to the current date. User may specify the date they want to set as well. :param date: Date value to set the last modified date to. This should be in the xsdDate form. This defaults to the current date if it is not provided. xsdDate Form: YYYY-MM-DDTHH:MM:SS :return: True :raises: IOCParseError if date format is not valid. """

        if date:
            match = re.match(DATE_REGEX, date)
            if not match:
                raise IOCParseError('last-modified date is not valid.  Must be in the form YYYY-MM-DDTHH:MM:SS')
        ioc_et.set_root_lastmodified(self.root, date)
        return True