title: Label objects not found
body: <p>Setup a graph using matplotlib which is working properly (see image below), but when I try to add a legend I get the following error: <code>UserWarning: No labeled objects found. Use label='...' kwarg on indivial plots.</code></p>
  
  <p>Here's the code I'm using to define the lines that I want in the legend and draw the legend:</p>
  
  <pre><code>#Moving average labels
  smaLabel1 = str(SMA1)+'d SMA'
  smaLabel2 = str(SMA2)+'d SMA'
  smaLabel3 = str(SMA3)+'d SMA'
  
  #Add SMAs to chart
  ax1.plot(ind, avg1, '#5998ff', label=smaLabel1, linewidth=1)
  ax1.plot(ind, avg2, '#ffbb82', label=smaLabel2, linewidth=1)
  ax1.plot(ind, avg3, '#d689c4', label=smaLabel3, linewidth=1)
  """ End SMA additions """
  
  #Add legend
  plt.legend()
  </code></pre>
  
  <p>I've checked the <code>smaLabel</code> variables, and all hold the correct strings. Anyone know why the labels aren't registering?</p>
  
  <p><img src="https://i.stack.imgur.com/wQyGF.png" alt="enter image description here"></p>