diff -r c6a5009ed04a -r ae189674bdad mercurial/statprof.py
--- a/mercurial/statprof.py	Thu Feb 28 07:45:51 2019 -0800
+++ b/mercurial/statprof.py	Sat Mar 02 12:51:04 2019 -0800
@@ -203,7 +203,7 @@
 class CodeSite(object):
     cache = {}
 
-    __slots__ = (u'path', u'lineno', u'function', u'source')
+    __slots__ = (r'path', r'lineno', r'function', r'source')
 
     def __init__(self, path, lineno, function):
         assert isinstance(path, bytes)
@@ -263,7 +263,7 @@
         return r'%s:%s' % (self.filename(), self.function)
 
 class Sample(object):
-    __slots__ = (u'stack', u'time')
+    __slots__ = (r'stack', r'time')
 
     def __init__(self, stack, time):
         self.stack = stack