example.cs

namespace System {
    public struct DateTime {
        public DateTime(int year, int month, int day, int hour, int minute, int second, int millisecond, int microsecond);
        public DateTime(int year, int month, int day, int hour, int minute, int second, int millisecond, int microsecond, System.DateTimeKind kind);
        public DateTime(int year, int month, int day, int hour, int minute, int second, int millisecond, int microsecond, System.Globalization.Calendar calendar);
        public int Microsecond { get; }
        public int Nanosecond { get; }
        public DateTime AddMicroseconds(double value);
    }
}