title: How to create a legend for a seaborn lineplot with two separately calculated lines
body: <p>I have the following lineplot and I need to create a legend for the two lines.
  My problem is that I can't figure out how to use legend() with the two lines.</p>
  
  <p>What I would like is having the legend box outside the graph with the "revenue" for the rvn line and "budget" for the bgt line.</p>
  
  <p>I have tried </p>
  
  <p><code>plt.legend(handles=[bgt, rvn])</code> </p>
  
  <p>and </p>
  
  <p><code>plt.legend((bgt, rvn), ('Budget', 'Revenue'))</code>, </p>
  
  <p>but they didn't work.</p>
  
  <pre><code>bgt = sns.lineplot(x= 'release_year', y='budget_adj_avg', data= df_bpr_avg) # blue
  rvn = sns.lineplot(x= 'release_year', y='revenue_adj_avg', data= df_bpr_avg);# orange
  plt.xlabel("Release year")
  plt.ylabel("Amount ($)")
  plt.title("Comparison average movies Budget and Revenue per year")
  #plt.legend((bgt, rvn), ('Budget', 'Revenue'))
  plt.legend(handles=[bgt, rvn])
  plt.show()
  </code></pre>