建立能重复运行的 Python 练习环境

import java.util.*;
public class Main {
    record V(int major,int minor,int patch) implements Comparable<V> {
        V { if (major<0 || minor<0 || patch<0) throw new IllegalArgumentException("negative version"); }
        public int compareTo(V b) {
            int c=Integer.compare(major,b.major); if(c!=0)return c;
            c=Integer.compare(minor,b.minor); return c!=0?c:Integer.compare(patch,b.patch);
        }
        public String toString(){return major+"."+minor+"."+patch;}
    }
    record Range(V lo,V hi) {
        Range { Objects.requireNonNull(lo);Objects.requireNonNull(hi);
            if(lo.compareTo(hi)>=0)throw new IllegalArgumentException("invalid interval"); }
    }
    static Optional<V> choose(List<Range> ranges,List<V> installed) {
        V lo=null,hi=null;
        for(Range r:ranges){
            // 左端取最大、右端取最小，保留全部约束的共同部分。
            if(lo==null||r.lo.compareTo(lo)>0)lo=r.lo;
            if(hi==null||r.hi.compareTo(hi)<0)hi=r.hi;
        }
        V best=null;
        for(V v:installed){
            Objects.requireNonNull(v);
            boolean ok=(lo==null||v.compareTo(lo)>=0)&&(hi==null||v.compareTo(hi)<0);
            if(ok&&(best==null||v.compareTo(best)>0))best=v;
        }
        return Optional.ofNullable(best);
    }
    static void check(String expected,Optional<V> got){
        if(!expected.equals(got.map(V::toString).orElse("NONE")))throw new AssertionError(got);
    }
    public static void main(String[] args){
        V a=new V(3,10,0),b=new V(3,12,0),c=new V(3,11,2);
        check("3.11.2",choose(List.of(new Range(a,b)),List.of(a,b,c)));
        check("NONE",choose(List.of(new Range(a,b)),List.of(b)));// 不包含上界。
        check("NONE",choose(List.of(new Range(a,c),new Range(c,b)),List.of(c)));
        check("NONE",choose(List.of(),List.of()));
        check("3.12.0",choose(List.of(),List.of(c,b)));// 无约束选最大。
        try{new Range(b,a);throw new AssertionError();}catch(IllegalArgumentException expected){}
        System.out.println("PASS 6 tests");
    }
}