title: how to select combobox item based on values on other widget in pyqt
body: <p>I have a lineEdit and a combobox.</p>
  
  <p>I have data as below</p>
  
  <pre><code>---------------------
  |ID    | DisplayName|
  ---------------------
  |100   | OneHundred |
  |150   | OneFifty   |
  |25    | TwendyFive |
  ---------------------
  </code></pre>
  
  <p>I added DisplayNames as items in combobox.</p>
  
  <p>I want to do as below </p>
  
  <p>when i enter 100 in lineedit, then "OneHundred" item to be selected in combobox
  when i enter 25 in lineedit, then "TwentyFive" item to be selected in combobox</p>
  
  <p>it should work like this.</p>
  
  <p>Can any one suggest a method to achieve this.... </p>