title: pie chart position and tight_layout() in Matplotlib
body: <p>I try to change pie chart position inside subplot in Matplotlib using <code>set_position</code>. Here is an example:</p>
  
  <pre><code>from pylab import *
  
  fig = figure()
  ax1 = fig.add_subplot(221)
  hist(random(35))
  
  ax2 = fig.add_subplot(222)
  hist(random(35))
  
  ax1 = fig.add_subplot(223)
  hist(random(35))
  
  ax4 = fig.add_subplot(224,aspect=1)
  labels = ['a', 'b', 'c', 'long long label ......', 'd']
  x = [118, 53, 48, 29, 20]
  pie(x, labels=labels)
  ax4.set_position([0.1, 0.1, 0.8, 0.8])
  tight_layout(rect=[0,0,1,1])
  show()
  </code></pre>
  
  <p>When I use <code>set_position</code> with <code>tight_layout</code> I get ugly result. How to change pie chart position correctly with <code>tight_layout</code>?</p>