title: AttributeError using python module py3270
body: <p>As a part of some automation I am trying to connect to mainframe using python, where I can access the mainframe files and create a
  report. Just like using mainframe files as DB for python program.</p>
  
  <p>To login to mainframe - we need to provide host details(xyz.host.com)
  followed with region details(h123p) and then with our credentials.</p>
  
  <p>I found that we can do this using python package py3270 and tried doing it but getting the error.</p>
  
  <pre><code>from py3270 import Emulator
  
  # or not (uses s3270)
  em = Emulator()
  
  em.connect('xyx.example.com')
  em.fill_field(3, 1, 'xxxx',5)
  em.send_enter()
  em.fill_field(2, 1, 'xxxxxxx', 7)
  em.send_enter()
  em.fill_field(8, 20, 'xxxxxxxx', 8)
  em.send_enter()
  
  # if your host unlocks the keyboard before truly being ready you can use:
  em.wait_for_field()
  
  # maybe look for a status message
  if not em.string_found(1, 2, 'login succesful'):
  abort()
  
  # do something useful
  
  # disconnect from host and kill subprocess
  em.terminate()
  </code></pre>
  
  <p>The error:</p>
  
  <pre><code>File "C:/Users/vganr/PycharmProjects/test/mainframe.py", line 6, in    
  &lt;module&gt;
  em = Emulator()
  File "C:\Program Files (x86)\Python37-32\lib\site-packages\py3270  
  \__init__.py", line 273, in __init__
  self.app = app or self.create_app(visible, args)
  File "C:\Program Files (x86)\Python37-32\lib\site-packages\py3270
  \__init__.py", line 291, in create_app
  return Ws3270App(args)
  File "C:\Program Files (x86)\Python37-32\lib\site-packages\py3270   
  \__init__.py", line 140, in __init__
  self.spawn_app()
  File "C:\Program Files (x86)\Python37-32\lib\site-packages\py3270  
  \__init__.py", line 145, in spawn_app
  args, stdin=subprocess.PIPE, stdout=subprocess.PIPE,   
  stderr=subprocess.PIPE
  File "C:\Program Files (x86)\Python37-32\lib\subprocess.py", line 775,   
  in __init__
  restore_signals, start_new_session)
  File "C:\Program Files (x86)\Python37-32\lib\subprocess.py", line 1178,  
  in _execute_child
  startupinfo)
  
  FileNotFoundError: [WinError 2] The system cannot find the file specified
  Exception ignored in: &lt;function Emulator.__del__ at 0x038CB810&gt;
  Traceback (most recent call last):
  File "C:\Program Files (x86)\Python37-32\lib\site-packages\py3270     
  \__init__.py", line 285, in __del__
  self.terminate()
  File "C:\Program Files (x86)\Python37-32\lib\site-packages\py3270   
  \__init__.py", line 320, in terminate
  if not self.is_terminated:
  
  AttributeError: 'Emulator' object has no attribute 'is_terminated'
  </code></pre>