title: saving figures using plt.savefig on colaboratory
body: <p>I am using collaboratory(online jupyter notebook) 
  I have the following code i am plotting some graphs using this functions and want to save plots locally 
  how can I do this ?</p>
  
  <pre><code>def make_plot_comparison(Xlabel,Ylabel,l1,l2,l1_title,l2_title,name): 
      plt.xlabel(Xlabel)
      plt.ylabel(Ylabel)
      plt.plot(l1,label=l1_title)
      plt.plot(l2,label=l2_title)
      plt.legend(loc='center right')
      plt.title(name)
      #plt.xlim(-5, 25)
      plt.savefig("abc.png")
      plt.show()
  </code></pre>