diff --git a/IPython/nbconvert/utils/lexers.py b/IPython/nbconvert/utils/lexers.py
index 97371b6..652d2f1 100644
--- a/IPython/nbconvert/utils/lexers.py
+++ b/IPython/nbconvert/utils/lexers.py
@@ -58,6 +58,7 @@ ipython_tokens = [
   (r'(%)(\w+)(.*\n)', bygroups(Operator, Keyword, Text)),
   (r'^(!!)(.+)(\n)', bygroups(Operator, using(BashLexer), Text)),
   (r'((?!=)!)(.+)(\n)', bygroups(Operator, using(BashLexer), Text)),
+  (r'^(\s*)(\?\??)(\s*%{0,2}[\w\.\*]*)', bygroups(Text, Operator, Text)),
 ]
 
 def build_ipy_lexer(python3):