#include<bits/stdc++.h>
using namespace std;
int n,sum,cnt;
char mp[310][310];
void work() {
    scanf("%d",&n);
    sum=cnt=0;
    for(int i=1;i<=n;i++)
        for(int j=1;j<=n;j++) {
            cin>>mp[i][j];
            if(mp[i][j]=='X'||mp[i][j]=='O') sum++;
        }
    cnt=0;
    for(int i=1;i<=n;i++)
        for(int j=1;j<=n;j++)
            if(((i-1)+(j-1))%3==0&&mp[i][j]=='X') cnt++;
            else if(((i-1)+(j-1))%3==1&&mp[i][j]=='O') cnt++;
    if(cnt<=sum/3) {
        for(int i=1;i<=n;i++) {
            for(int j=1;j<=n;j++) {
                if(((i-1)+(j-1))%3==0&&mp[i][j]=='X') putchar('O');
                else if(((i-1)+(j-1))%3==1&&mp[i][j]=='O') putchar('X');
                else printf("%c",mp[i][j]);
            }
            puts("");
        }
        return;
    }
    cnt=0;
    for(int i=1;i<=n;i++)
        for(int j=1;j<=n;j++)
            if(((i-1)+(j-1))%3==1&&mp[i][j]=='X') cnt++;
            else if(((i-1)+(j-1))%3==2&&mp[i][j]=='O') cnt++;
    if(cnt<=sum/3) {
        for(int i=1;i<=n;i++) {
            for(int j=1;j<=n;j++) {
                if(((i-1)+(j-1))%3==1&&mp[i][j]=='X') putchar('O');
                else if(((i-1)+(j-1))%3==2&&mp[i][j]=='O') putchar('X');
                else printf("%c",mp[i][j]);
            }
            puts("");
        }
        return;
    }
    cnt=0;
    for(int i=1;i<=n;i++)
        for(int j=1;j<=n;j++)
            if(((i-1)+(j-1))%3==2&&mp[i][j]=='X') cnt++;
            else if(((i-1)+(j-1))%3==0&&mp[i][j]=='O') cnt++;
    if(cnt<=sum/3) {
        for(int i=1;i<=n;i++) {
            for(int j=1;j<=n;j++) {
                if(((i-1)+(j-1))%3==2&&mp[i][j]=='X') putchar('O');
                else if(((i-1)+(j-1))%3==0&&mp[i][j]=='O') putchar('X');
                else printf("%c",mp[i][j]);
            }
            puts("");
        }
        return;
    }
}
signed main() {
	int t;scanf("%d",&t);
	while(t--) work();
}