Compare compares the current DateTime instance with u.
If the current instance is before u, it returns -1.
If the current instance is after u, it returns +1.
If they're the same, it returns 0.
Equal reports whether the current DateTime and u represent the same time instant.
Two DateTime can be equal even if they are in different locations.
For example, 6:00 +0200 and 4:00 UTC are Equal.
DateTime represents a [time.Time] instance in UTC that is wrapped and serialized using the app default date layout.