title: How to use where conditon based on string values in a pandas dataframe?
body: <p>How do I use multiple conditions to correct values in my dataframe</p>
  <p>I want to change</p>
  <ul>
  <li>Apple = Fruit</li>
  <li>Potato = Veg</li>
  </ul>
  <p>My data frame is like this</p>
  <pre><code>      Item      Category
        Apple     Freshco
        Potato    Sobeys
        Orange    Fruit
        Banana    Fruit
  </code></pre>
  <p>I want to change the two categories so the dataframe is like this</p>
  <pre><code>      Item      Categroy
        Apple     Fruit
        Potato    Veg
        Orange    Fruit
        Banana    Fruit  
  </code></pre>