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#include<stdio.h>
#define mod 1000000007
#include<string.h>
#include<algorithm>
using namespace std;
int dp[1111][1111];
char str[6666];
int main()
{
int t;
scanf("%d",&t);
while(t--)
{
int n;
scanf("%d",&n);
scanf(" %s",str+1);
memset(dp,0,sizeof(dp));
for(int i=0; i<=n; i++)
for(int j=0; j<=n; j++)
{
if(i||j)
{
if(str[i+j]=='W')
{
if(i%2==1)
dp[i][j]+=dp[i-1][j]%mod;
if(j%2==1)
dp[i][j]+=dp[i][j-1]%mod;
}
else if(str[i+j]=='B')
{
if(i%2==0&&i)
dp[i][j]+=dp[i-1][j]%mod;
if(j%2==0&&j)
dp[i][j]+=dp[i][j-1]%mod;
}
}
else dp[i][j]=1;
}
printf("%d\n",dp[n][n]%mod);
}
}