/// DO NOT MODIFY. Auto-generated file
/// A Timestamp represents a point in time independent of any time zone or local
/// calendar, encoded as a count of seconds and fractions of seconds at
/// nanosecond resolution. The count is relative to an epoch at UTC midnight on
/// January 1, 1970, in the proleptic Gregorian calendar which extends the
/// Gregorian calendar backwards to year one.
///
/// All minutes are 60 seconds long. Leap seconds are "smeared" so that no leap
/// second table is needed for interpretation, using a [24-hour linear
/// smear](<https://developers.google.com/time/smear>).
///
/// The range is from 0001-01-01T00:00:00Z to 9999-12-31T23:59:59.999999999Z. By
/// restricting to that range, we ensure that we can convert to and from [RFC
/// 3339](<https://www.ietf.org/rfc/rfc3339.txt>) date strings.
///
/// # Examples
///
/// Example 1: Compute Timestamp from POSIX `time()`.
///
/// Timestamp timestamp;
/// timestamp.set_seconds(time(NULL));
/// timestamp.set_nanos(0);
///
/// Example 2: Compute Timestamp from POSIX `gettimeofday()`.
///
/// struct timeval tv;
/// gettimeofday(&tv, NULL);
///
/// Timestamp timestamp;
/// timestamp.set_seconds(tv.tv_sec);
/// timestamp.set_nanos(tv.tv_usec * 1000);
///
/// Example 3: Compute Timestamp from Win32 `GetSystemTimeAsFileTime()`.
///
/// FILETIME ft;
/// GetSystemTimeAsFileTime(&ft);
/// UINT64 ticks = (((UINT64)ft.dwHighDateTime) << 32) | ft.dwLowDateTime;
///
/// // A Windows tick is 100 nanoseconds. Windows epoch 1601-01-01T00:00:00Z
/// // is 11644473600 seconds before Unix epoch 1970-01-01T00:00:00Z.
/// Timestamp timestamp;
/// timestamp.set_seconds((INT64) ((ticks / 10000000) - 11644473600LL));
/// timestamp.set_nanos((INT32) ((ticks % 10000000) * 100));
///
/// Example 4: Compute Timestamp from Java `System.currentTimeMillis()`.
///
/// long millis = System.currentTimeMillis();
///
/// Timestamp timestamp = Timestamp.newBuilder().setSeconds(millis / 1000)
/// .setNanos((int) ((millis % 1000) * 1000000)).build();
///
///
/// Example 5: Compute Timestamp from Java `Instant.now()`.
///
/// Instant now = Instant.now();
///
/// Timestamp timestamp =
/// Timestamp.newBuilder().setSeconds(now.getEpochSecond())
/// .setNanos(now.getNano()).build();
///
///
/// Example 6: Compute Timestamp from current time in Python.
///
/// timestamp = Timestamp()
/// timestamp.GetCurrentTime()
///
/// # JSON Mapping
///
/// In JSON format, the Timestamp type is encoded as a string in the
/// [RFC 3339](<https://www.ietf.org/rfc/rfc3339.txt>) format. That is, the
/// format is "{year}-{month}-{day}T{hour}:{min}:{sec}\[.{frac_sec}\]Z"
/// where {year} is always expressed using four digits while {month}, {day},
/// {hour}, {min}, and {sec} are zero-padded to two digits each. The fractional
/// seconds, which can go up to 9 digits (i.e. up to 1 nanosecond resolution),
/// are optional. The "Z" suffix indicates the timezone ("UTC"); the timezone
/// is required. A proto3 JSON serializer should always use UTC (as indicated by
/// "Z") when printing the Timestamp type and a proto3 JSON parser should be
/// able to accept both UTC and other timezones (as indicated by an offset).
///
/// For example, "2017-01-15T01:30:15.01Z" encodes 15.01 seconds past
/// 01:30 UTC on January 15, 2017.
///
/// In JavaScript, one can convert a Date object to this format using the
/// standard
/// \[toISOString()\](<https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/toISOString>)
/// method. In Python, a standard `datetime.datetime` object can be converted
/// to this format using
/// \[`strftime`\](<https://docs.python.org/2/library/time.html#time.strftime>) with
/// the time format spec '%Y-%m-%dT%H:%M:%S.%fZ'. Likewise, in Java, one can use
/// the Joda Time's \[`ISODateTimeFormat.dateTime()`\](
/// <http://www.joda.org/joda-time/apidocs/org/joda/time/format/ISODateTimeFormat.html#dateTime%2D%2D>
/// ) to obtain a formatter capable of generating timestamps in this format.
///
///