title: tkinter: getting index of selected text in textbox from 1st char
body: <p>How do I get the position of selected text from the 1st character in the string. When I do </p>
  
  <pre><code> ind = textwidget.index("self.first")
  </code></pre>
  
  <p>I only get index as line.column. What I would like to have is the number of characters from the start of the first character. The motivation for doing this way is that I do not have to bother the way formatting is done in the UI which results in number of lines (together with newline chars in string).</p>
  
  <p>Is it possible ?</p>