title: Matplotlib multiple broken axis
body: <p>I'm trying to make a plot with 2 breaks in the x-axis. I can produce one break following the matplotlib</p>
  <pre><code>days = list(range(0,500))
  values = list(np.random.randint(low = 10,high=100,size=len(days)))
  
  fig = plt.figure(figsize=(5, 5))
  
  f,(ax,ax2) = plt.subplots(1,2,sharey=True, facecolor='w')
  
  ax.plot(days, values)
  ax2.plot(days, values)
  
  ax.set_xlim(0,100)  # x-axis range limited to 0 - 100 
  ax2.set_xlim(250, 300)  # x-axis range limited to 250 - 300
  
  # hide the spines between ax and ax2
  ax.spines['right'].set_visible(False)
  ax2.spines['left'].set_visible(False)
  ax.yaxis.tick_left()
  ax.tick_params(labelright='off')
  
  d = .015 # how big to make the diagonal lines in axes coordinates
  # arguments to pass plot, just so we don't keep repeating them
  kwargs = dict(transform=ax.transAxes, color='k', clip_on=False)
  ax.plot((1-d,1+d), (-d,+d), **kwargs)
  ax.plot((1-d,1+d),(1-d,1+d), **kwargs)
  
  kwargs.update(transform=ax2.transAxes)  # switch to the bottom axes
  ax2.plot((-d,+d), (1-d,1+d), **kwargs)
  ax2.plot((-d,+d), (-d,+d), **kwargs)
  
  plt.show()
  </code></pre>
  <p><a href="https://i.stack.imgur.com/5kPD1.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/5kPD1.png" alt="enter image description here" /></a></p>
  <p>However, how can I modify this to have another break to have an <code>ax3</code> between 400 and 500? Additionally, how can I scale the x-axis length to be reflective of the length of the interval? In the above I would ideally like the right side reduced as it is half the interval.</p>
  <p>I have tried using the brokenaxes which looks like it would meet the criteria automatically scaling and allowing multiple breaks refer to here e.g. <a href="https://test-brokenaxes.readthedocs.io/en/latest/auto_examples/plot_usage.html#sphx-glr-auto-examples-plot-usage-py" rel="nofollow noreferrer">https://test-brokenaxes.readthedocs.io/en/latest/auto_examples/plot_usage.html#sphx-glr-auto-examples-plot-usage-py</a></p>
  <p>However, when running that code I get</p>
  <pre><code>AttributeError: 'SubplotSpec' object has no attribute 'is_last_row'
  </code></pre>
  <p>Any assistance appreciated.</p>