title: How to create a list of strings in python from two "array.flatten()"-ed lists
body: <p>I'm looking to create the following list in python:</p>
  
  <pre><code>list = ["pix420_615", "pix421_615", ... , "pix425_620"]
  </code></pre>
  
  <p>N.B. Where the list is a list of strings, not values.</p>
  
  <p>From the following two lists:</p>
  
  <pre><code>x= [420, 421, 422, 423, 424, 425, 420, 421, 422, 423, 424, 425, 420, 421, 422, 423, 424, 425,
   420, 421, 422, 423, 424, 425, 420, 421, 422, 423, 424, 425, 420, 421, 422, 423, 424, 425]
  
  y= [615, 615, 615, 615, 615, 615, 616, 616, 616, 616, 616, 616, 617, 617, 617, 617, 617, 617,
   618, 618, 618, 618, 618, 618, 619, 619, 619, 619, 619, 619, 620, 620, 620, 620, 620, 620]
  </code></pre>
  
  <p>I was wondering how I would go about doing this, and maintain the consistency of corresponding array values...?</p>