estimatedHeightForText.swift

    func estimatedFrame(forText text: String) -> CGRect {
        // width is same as cell.texView width
        //height is an arbitrary larg value
        let size = CGSize(width: 200, height: 1000)
        let options = NSStringDrawingOptions.usesFontLeading.union(.usesLineFragmentOrigin)
        let attributes = [NSAttributedStringKey.font: UIFont.systemFont(ofSize: 16)]
        return  NSString(string: text).boundingRect(with: size, options: options, attributes: attributes, context: nil)
    }