title: Python Combine Elements in one List With All Elements in Another
body: <p>Given the following lists:</p>
  
  <pre><code>a = ['a','b']
  b = [1,2,3,4]
  </code></pre>
  
  <p>I'd like to produce this:</p>
  
  <pre><code>c = ['a1','a2','a3','a4','b1','b2','b3','b4']
  </code></pre>
  
  <p>So I basically want to join every element of b to each element in a.</p>
  
  <p>I'd like an approach similar to this:</p>
  
  <pre><code>[x+str(y) for x in a and y in b]
  </code></pre>
  
  <p>Thanks in advance!</p>