title: How to delete pandas values based on condition and accordingly shift the rows
body: <p>For examples, I have a DataFrame like this:</p>
  
  <pre><code>       Rank #1       Rank #2      Rank #3        Rank #4     status 
  0        A             B            D               C          in
  1        B             C            A               D          out
  2        A             D            C               B          in
  3        A             B            C               D          out
  4        D             C            B               A          out
  5        D             A            C               B          out 
  ...
  </code></pre>
  
  <p>How can I delete A values if <code>status == out</code> and then shift the other row ranking values to the left?</p>
  
  <p>My expected outcome is:</p>
  
  <pre><code>     Rank #1       Rank #2      Rank #3        Rank #4     status 
  0        A             B            D               C        in
  1        B             C            D                        out
  2        A             D            C               B        in
  3        B             C            D                        out
  4        D             C            B                        out
  5        D             C            B                        out
  ...
  </code></pre>