diff -r 5877c191b76e Lib/fractions.py
--- a/Lib/fractions.py	Fri Oct 16 12:21:37 2015 -0700
+++ b/Lib/fractions.py	Fri Oct 16 23:58:52 2015 +0300
@@ -453,7 +453,10 @@
 
     def __floordiv__(a, b):
         """a // b"""
-        return math.floor(a / b)
+        if isinstance(b, numbers.Complex):
+            return math.floor(a / b)
+        else:
+            return NotImplemented
 
     def __rfloordiv__(b, a):
         """a // b"""
@@ -461,8 +464,11 @@
 
     def __mod__(a, b):
         """a % b"""
-        div = a // b
-        return a - b * div
+        if isinstance(b, numbers.Complex):
+            div = a // b
+            return a - b * div
+        else:
+            return NotImplemented
 
     def __rmod__(b, a):
         """a % b"""