title: How to check if a product is a simple product
body: <p>I know how to check if a product is configurable or not. I also got how to check if a simple product is a child of a configurable product or not. But can anyone tell me how to check if a product is a pure simple product?</p>
  
  <p>That means that I want to check those products which I created as <code>Attribute set='Default'</code> and <code>Product type='Simple Product'</code> not <code>attribute set='Default'</code> and <code>Product type='configurable Product'</code>.</p>