title: Spark dataframe insert values if doesn't exist
body: <p>Suppose I have dataframe like this:</p>
  
  <p><a href="https://i.stack.imgur.com/UuF61.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/UuF61.png" alt="enter image description here"></a></p>
  
  <p>but sometimes some rows are missing I need to dermine what rows are missing and then insert such row.All the values are known
  What is best way to do it in Spark(prefer in python)</p>