title: Pandas: How to create master link records for all matched values in in multiple rows?
body: <p>Let's say I have a data frame as below with value pairs in 2 columns.</p>
  
  <pre><code>A       B
  182269  182270  
  654372  654374
  619300  619301
  654373  654374
  </code></pre>
  
  <p>I want to add another column that has row value representing all matched values in the pair of same row and all values in other rows matched by this pair of values.</p>
  
  <p>Below is the expected result:</p>
  
  <pre><code>A       B       C
  182269  182270  182269, 182270
  654372  654374  654372, 654373, 654374
  619300  619301  619300, 619301
  654373  654374  654372, 654373, 654374
  </code></pre>
  
  <p>Can you please advice? Thanks in advance!</p>