diff --git a/bitbake/lib/bb/data_smart.py b/bitbake/lib/bb/data_smart.py
index 67af38050e..297a2f45b4 100644
--- a/bitbake/lib/bb/data_smart.py
+++ b/bitbake/lib/bb/data_smart.py
@@ -39,10 +39,10 @@ from bb.COW  import COWDictBase
 logger = logging.getLogger("BitBake.Data")
 
 __setvar_keyword__ = ["_append", "_prepend", "_remove"]
-__setvar_regexp__ = re.compile('(?P<base>.*?)(?P<keyword>_append|_prepend|_remove)(_(?P<add>[^A-Z]*))?$')
+__setvar_regexp__ = re.compile(r'(?P<base>.*?)(?P<keyword>_append|_prepend|_remove)(_(?P<add>[^A-Z]*))?$')
 __expand_var_regexp__ = re.compile(r"\${[^{}@\n\t :]+}")
 __expand_python_regexp__ = re.compile(r"\${@.+?}")
-__whitespace_split__ = re.compile('(\s)')
+__whitespace_split__ = re.compile(r'(\s)')
 
 def infer_caller_details(loginfo, parent = False, varval = True):
     """Save the caller the trouble of specifying everything."""