title: How to access IDL system variables that starts with '!' with IDL-Python bridge?
body: <p>I am trying to use IDL-Python bridge to call IDL (Interactive Data Language) procedures from Python.
  Could anybody tell how to access IDL system variables that starts with '!' from Python? For example, a call in Python</p>
  
  <pre><code>from idlpy import *
  
  d2r = IDL.!DDTOR 
  </code></pre>
  
  <p>gives SyntaxError: invalid syntax.</p>