title: Using regex to detect a sku
body: <p>I'm new to regex and I have some trouble dectecting the sku (unique ids) of a product in a column. 
  My skus can take any form: all they have in common basically is:</p>
  
  <ol>
  <li>to be words made of a combination of letters and numbers</li>
  <li>to have 6 characters</li>
  </ol>
  
  <p>Here is an example of what I have in my column:</p>
  
  <pre><code>LX0051
  N41554
  shoes
  handbag
  1B1F25
  1V1F8L
  store near me
  M90947
  M90844
  </code></pre>
  
  <p>How can I identify the rows that contain a sku using regex?</p>