title: Python os.system returns 103
body: <p>I'm trying to call a py script (let say sub-script) within a main-script via</p>
  
  <pre><code>os.system('script_customer_update')
  </code></pre>
  
  <p>When I'm call the main script it runs through without any exception and the sub-script wasn't performed.</p>
  
  <p>When I'm call the Python Shell and put in the following in</p>
  
  <pre><code>import os
  os.system('script_customer_update')
  </code></pre>
  
  <p>I'm receiving a returncode 103</p>
  
  <p>When I open the sub-script direct and run it via F5, it runs through without any exceptions.</p>
  
  <p>Any idea what is wrong?
  Python 3 is installed.</p>