title: Problems with matplotlib.pyplot.xticks()
body: <p>I am trying to plot boxplots as follows:</p>
  
  <pre><code>import matplotlib.pyplot as plt
  
  plt.figure()
  plt.xlabel("X")
  plt.ylabel("Y")
  plt.xticks([1,2,3,4], ["a", "b", "c", "d"])
  plt.boxplot(data)
  plt.show()
  </code></pre>
  
  <p>However, I got an error for <code>plt.xticks</code> where it says tuple object is not callable. My x-axis is labelled with 1,2,3,4 instead of 'a', 'b', 'c', 'd'. </p>
  
  <p>I am following a tutorial here: <a href="https://matplotlib.org/devdocs/gallery/ticks_and_spines/ticklabels_rotation.html#sphx-glr-gallery-ticks-and-spines-ticklabels-rotation-py" rel="nofollow noreferrer">Rotating custom tick labels</a></p>