code: public GeneralTimestamp<IndianCalendar> atTime(
          int hour,
          int minute
      ) {
  
          return this.at(PlainTime.of(hour, minute));
  
      }
docs: /*[deutsch]
  <p>Entspricht {@code at(PlainTime.of(hour, minute))}. </p>
  
  @param   hour        hour of day in range (0-24)
  @param   minute      minute of hour in range (0-59)
  @return  general timestamp as composition of this date and given time
  @throws  IllegalArgumentException if any argument is out of range