title: Python: expand list of strings by adding n elements for each original element
body: <p>I have the following list of strings:</p>
  <pre><code>l1 = ['one','two','three']
  </code></pre>
  <p>I want to obtain a list that has, say, these same elements repeated <code>n</code> times. If <code>n=3</code> I'd get:</p>
  <pre><code>l2 = ['one','one','one','two','two','two','three','three','three']
  </code></pre>
  <p>What I am trying is this:</p>
  <pre><code>l2 = [3*i for i in l1]
  </code></pre>
  <p>But what I obtain is this:</p>
  <pre><code>l2 = ['oneoneone','twotwotwo','threethreethree']
  </code></pre>
  <p>If I try this:</p>
  <pre><code>l2 = [3*(str(i)+&quot;,&quot;) for i in l1]
  </code></pre>
  <p>I obtain:</p>
  <pre><code>l2 = ['one,one,one','two,two,two','three,three,three']
  </code></pre>
  <p>What am I missing?</p>