title: Passing variable from bash-python-bash
body: <p>To use logarithmic function, I used export to pass a variable <code>$var1</code> from bash to python script. After the calculation, I used</p>
  
  <pre><code>  os.environ['var1']=str(result)
  </code></pre>
  
  <p>to send the result back to bash script.
  However, the bash still shows the unmodified value. </p>