<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def timestamp_localize(value):
 """ Save timestamp as utc :param value: Timestamp (in UTC or with tz_info) :type value: float | datetime.datetime :return: Localized timestamp :rtype: float """

        if isinstance(value, datetime.datetime):
            if not value.tzinfo:
                value = pytz.UTC.localize(value)
            else:
                value = value.astimezone(pytz.UTC)
            # Assumes utc (and add the microsecond part)
            value = calendar.timegm(value.timetuple()) + \
                value.microsecond / 1e6
        return value