title: Matplotlib: Annotate Subplots in a Figure with A, B, C
body: <p>When submitting papers to scientific journals one quite frequently needs to enumerate the different subplots of a figure with A, B, ... . </p>
  
  <p><img src="https://i.stack.imgur.com/Rzp0A.png" alt="enter image description here"></p>
  
  <p>This sounds like a very common problem and I was trying to find an elegant way to do that automatically with matplotlib, but I was surprised to find nothing on it. But maybe I am not using the right search terms. Ideally, I am searching for a way to annotate such that the letters stay in place relative to the subplot if the figure is resized or the subplot is moved via <code>fig.subplots_adjust</code>, <code>fig.tight_layout</code>, or similar.</p>
  
  <p>Any help or solution will appreciated.</p>