#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <cmath>
#include <ctime>
#include <iostream>
#include <algorithm>
#include <string>
#include <vector>
#include <deque>
#include <list>
#include <set>
#include <map>
#include <stack>
#include <queue>
#include <numeric>
#include <iomanip>
#include <bitset>
#include <sstream>
#include <fstream>
#include <limits.h>
#define debug "output for debug\n"
#define pi (acos(-1.0))
#define eps (1e-6)
#define inf (1<<28)
#define sqr(x) (x) * (x)
#define mod 1000000007
using namespace std;
typedef long long ll;
typedef unsigned long long ULL;
typedef pair<ll,ll> p;
map<p,ll> m;
struct point
{
    ll x,y;
}a[1005];
ll gcd(ll a,ll b)
{
    return b?gcd(b,a%b):a;
}
bool cmp(point a,point b)
{
    if(a.x==b.x)
        return a.y<b.y;
    return a.x<b.x;
}
int main()
{
    ll i,j,k,n,t;
    scanf("%I64d",&t);
    while(t--)
    {
        scanf("%I64d",&n);
        for(i=0;i<n;i++)
            scanf("%I64d%I64d",&a[i].x,&a[i].y);
        sort(a,a+n,cmp);
        ll ans=0;
        for(i=0;i<n;i++)
        {
            m.clear();
            for(j=i+1;j<n;j++)
            {
                ll dx=a[j].x-a[i].x;
                ll dy=a[j].y-a[i].y;
                ll d=gcd(dx,dy);
                dx=dx/d;
                dy=dy/d;
                m[make_pair(dx,dy)]++;
            }
            map<p,ll>::iterator it;
            for(it=m.begin();it!=m.end();it++)
            {
                k=it->second;
                if(k>=2)
                    ans=ans+k*(k-1)/2;
            }
        }
        printf("%I64d\n",ans);
    }
    return 0;
}

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