title: Using matplotlib, make date ticks not overlap
body: <p>I have dates for tick marks on my x-axis. How can I make them automatically not overlap?</p>
  
  <p>There are a lot of S.O. questions and posts about setting the tick interval - but this won't work for me since the date range for my plot can vary from 1 week, up to 1 year. </p>
  
  <p>When people have plots with highly variable ranges, what is the method to make the x-axis ticks automatically not overlap? </p>
  
  <pre><code>plt.plot(date_list, unique_list)
  plt.ylabel('# Uniques per day')
  </code></pre>
  
  <p><img src="https://i.stack.imgur.com/5BAVD.png" alt="enter image description here"></p>