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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 _datetime_to_rfc3339(value, ignore_zone=True):
 """Convert a timestamp to a string. :type value: :class:`datetime.datetime` :param value: The datetime object to be converted to a string. :type ignore_zone: bool :param ignore_zone: If True, then the timezone (if any) of the datetime object is ignored. :rtype: str :returns: The string representing the datetime stamp. """

    if not ignore_zone and value.tzinfo is not None:
        # Convert to UTC and remove the time zone info.
        value = value.replace(tzinfo=None) - value.utcoffset()

    return value.strftime(_RFC3339_MICROS)