Reclamation of Foreign Withholding Tax

Hi Experts,

 

I had held ADS shares/securities in an India-based company traded in the US, which until recently were no longer being traded on US exchanges. My shares were sold, and a significant amount/percentage was taken out of my sale amount from the India government as a withholding tax. What may I do to obtain the withholding amount, and to properly account for this on IRS tax forms. Thank you for your help and insights.