title: remove tick labels in Python but keep gridlines
body: <p>I have a Python script which is producing a plot consisting of 3 subplots all in 1 column.</p>
  
  <p>In the middle subplot, I currently have gridlines, but I want to remove the x axis tick labels.</p>
  
  <p>I have tried</p>
  
  <pre><code>ax2.axes.get_xaxis().set_ticks([])
  </code></pre>
  
  <p>but this seems to remove the gridlines also. </p>
  
  <p>How can I remove the tick labels and keep the gridlines please?</p>