def _ConvertToTimestamp(self, date, time, timezone):
    """Converts date and time values into a timestamp.

    The date and time are made up of two strings, the date and the time,
    separated by a tab. The time is in local time. The month and day can
    be either 1 or 2 characters long, e.g.: 7/30/2013\\t10:22:48 AM

    Args:
      date (str): date.
      time (str): time.
      timezone (pytz.timezone): timezone of the date and time.

    Returns:
      int: a timestamp integer containing the number of micro seconds since
          January 1, 1970, 00:00:00 UTC.

    Raises:
      TimestampError: if the timestamp is badly formed or unable to transfer
          the supplied date and time into a timestamp.
    """
    # TODO: check if this is correct, likely not date or not time
    # is more accurate.
    if not date and not time:
      raise errors.TimestampError(
          'Unable to extract timestamp from McAfee AV logline.')

    # TODO: Figure out how McAfee sets Day First and use that here.
    # The in-file time format is '07/30/2013\t10:22:48 AM'.
    try:
      time_string = '{0:s} {1:s}'.format(date, time)
    except UnicodeDecodeError:
      raise errors.TimestampError('Unable to form a timestamp string.')

    return timelib.Timestamp.FromTimeString(time_string, timezone=timezone)
Converts date and time values into a timestamp.

    The date and time are made up of two strings, the date and the time,
    separated by a tab. The time is in local time. The month and day can
    be either 1 or 2 characters long, e.g.: 7/30/2013\\t10:22:48 AM

    Args:
      date (str): date.
      time (str): time.
      timezone (pytz.timezone): timezone of the date and time.

    Returns:
      int: a timestamp integer containing the number of micro seconds since
          January 1, 1970, 00:00:00 UTC.

    Raises:
      TimestampError: if the timestamp is badly formed or unable to transfer
          the supplied date and time into a timestamp.