RuntimeError: main thread is not in main loop with Matplotlib and Flask : <p>I'm using flask, matplotlib to save image and tensorflow to create a session. I'm getting the above error when I run the following code. Does the flask route run on a separate thread? How can I make fig.saveFig piece of code run on the Main thread. Thanks a lot</p>

<pre><code> @app.route('/open', methods = ['GET', 'POST'])
 def sendOutput():
     global loss,a2,xP,yP,scale,sess,fig
     test_X,test_Y = own_model.getEvaluateData(scale)
     cost,ans = sess.run([loss,a2],feed_dict={xP:test_X,yP:test_Y})
     d = np.array(ans) - np.array(test_Y)
     val = hist(d,100)
     sess.close()
     fig.saveFig('abc.png') //Errror on this line
</code></pre>
