title: Convert Gregorian (Christian) date to Persian date and vice-versa in Python
body: <p>How can I convert <code>Gregorian date</code> to <code>Persian date</code> and vice-versa in <code>Python</code>?</p>
  
  <p><a href="https://github.com/behzadi/persianDatepicker" rel="noreferrer">All I found</a> was some widgets and stuffs which will create Persian Calendar. I don't want a Persian calendar. I just want to convert dates to each other.
  So how can I do that?</p>