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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 expireat(self, name, when):
 """ Set an expire flag on key ``name``. ``when`` can be represented as an integer indicating unix time or a Python datetime object. """

        if isinstance(when, datetime.datetime):
            when = int(mod_time.mktime(when.timetuple()))
        return self.execute_command('EXPIREAT', name, when)