title: join/combine similar columns in python
body: <p>I have this problem after I merged/combined multiple columns: </p>
  
  <pre><code>df = 
  Name    id  id_x    id_y    age age_x
  A   111 111     20  
  B   112     112     30
  C       113 113 40  40
  </code></pre>
  
  <p>My goal is to clean them up like this:</p>
  
  <pre><code>Name    id  age
  A   111 20
  B   112 30
  C   113 40
  </code></pre>
  
  <p>Thank you in advance!</p>