code: public final static Function<Long, Long> pow(int power, MathContext mathContext) {
          return new Pow(power, mathContext);
      }
docs: <p>
  It performs the operation target<sup>power</sup> and returns its value. The result
  precision and rounding mode is specified by the given {@link MathContext}
  </p>
  
  @param power the power to raise the target to
  @param mathContext the {@link MathContext} to specify precision and {@link RoundingMode}
  @return the result of target<sup>power</sup>