diff -r b8b47f9b5e56 -r 396da88d7b5c docutil/docpdf.py
--- a/docutil/docpdf.py	Fri Sep 22 10:57:57 2017 +0300
+++ b/docutil/docpdf.py	Fri Sep 22 16:37:38 2017 +0300
@@ -72,13 +72,13 @@
             return None
 
         readerexepath = os.path.join(readerpath, "AcroRd32.exe")
-        if(os.path.isfile(readerexepath)):
+        if os.path.isfile(readerexepath):
             open_win_pdf(readerexepath, pdffile, pagenum)
         else:
             return None
     else:
         readerexepath = os.path.join("/usr/bin", "xpdf")
-        if(os.path.isfile(readerexepath)):
+        if os.path.isfile(readerexepath):
             open_lin_pdf(readerexepath, pdffile, pagenum)
         else:
             wx.MessageBox("xpdf is not found or installed !")