title: Matplotlib: annotate() missing 1 required positional argument: 'self'
body: <p>I'm newbie in matplotlib and I'm trying to set a text to a point in a graph but I've got the error:</p>
  
  <blockquote>
    <p>Traceback (most recent call last):   File "main.py", line 239, in
    
        main()   File "main.py", line 232, in main
        p.show_graphic_ortg_drtg()   File "/home/josecarlos/Workspace/python/process/process.py", line 363, in
    show_graphic_ortg_drtg
        Axes.Axes.annotate(xy=(df[0:1]["ortg"], df[0:1]["drtg"]), s="Hola") TypeError: annotate() missing 1 required positional
    argument: 'self'</p>
  </blockquote>
  
  <p>My code is:</p>
  
  <pre><code>import matplotlib.axes as Axes
  
  Axes.Axes.annotate(xy=(df[0:1]["ortg"], df[0:1]["drtg"]), s="Message")
  </code></pre>
  
  <p>df is a DataFrame from Pandas previously generated.</p>
  
  <p>What am I doing wrong? I'm following some tutorials and documentation and I don't find the mistake.</p>