title: No Response After Running Python Script Using Python-Shell
body: <p>I have a nodeJS application and I need to run a python script in order to get a certain response. I am using python-shell in order to do that, but I am getting no response. </p>
  
  <p>I have tried also using a child-process, same response.</p>
  
  <p>Here I call the python script:</p>
  
  <pre><code>var ps = require('python-shell');
  ps.PythonShell.run('./face_detect.py', array1, function (err, data) {
      if (err) req.send(err);
      req.send(data.toString())
  }); 
  </code></pre>
  
  <p>This is a snippet of my python script:</p>
  
  <pre><code>import cv2
  import sys
  import os
  import numpy as np
  
  students = sys.argv[1]
  # get the names and put them in an array ---&gt; subjects
  imagePath = "class/welcome.jpg"
  cascPath = "haarcascade_frontalface_alt.xml"
  
  faceCascade = cv2.CascadeClassifier(cascPath)
  
  .....
  for (x, y, w, h) in faces:
      num = 0
      crop_img = cv2.UMat(image[y-40:y+h+100,x-40:x+h+40])
      cv2.imwrite("face" + str(num) + ".jpg", crop_img)
      test_img = cv2.imread("face" + str(num) + ".jpg")
      num = num + 1
      predicted_img1 = predict(test_img)
  absences["A"] = 1
  for name, a in absences.items():
      if a == 0:
          noshow.append(name)
  print(noshow)
  cv2.waitKey(0)
  
  </code></pre>
  
  <p>I expect it to return an array. 
  Can anyone help me with this?</p>