title: How to find line number of searched string in Tkinter Textbox and then insert string just before
body: <p>let's say i have a tkinter Textbox like this :</p>
  <p>textbox =</p>
  <pre><code>Hello world !
  Life is good on earth
  Winter is already there
  </code></pre>
  <p>How do i search for <code>&quot;good&quot;</code>, get the line number and insert something on the line number just before ?</p>
  <p>Expected result :</p>
  <pre><code>Hello world !
  New sentence inserted here
  Life is good on earth
  Winter is already there
  </code></pre>
  <p>I know how to use the <code>.find(&quot;good&quot;)</code> method to get the number of characters before &quot;good&quot; is reached but since i want to be able to use the <code>textbox.insert()</code> i need the line number (not the number of characters) like <code>1.0</code> to specify where i want to insert the new sentence in the textbox .</p>