title: Python ginput not allowing new points to be plotted
body: <p>This code asks the user to digitize three points (using ginput), then should plot those points to the screen atop the imshow plot. It does not. Any ideas why?</p>
  
  <pre><code>from pylab import show, ginput, rand, imshow, plot
  from matplotlib.figure import Figure
  import numpy as np
  
  x1 = rand(103, 53) 
  figure = Figure(figsize=(4, 4), dpi=100)
  axes = figure.add_subplot(111)
  
  imshow(x1)
  
  # Get user input
  x = ginput(3)
  x = np.array(x)
  
  # Plot the user's points to the screen
  plot(x[:, 0], x[:, 1], 'k*', ms=50)
  show()
  </code></pre>