diff --git a/cpe/comp/cpecomp2_3.py b/cpe/comp/cpecomp2_3.py
index bb8e133..a2042ba 100644
--- a/cpe/comp/cpecomp2_3.py
+++ b/cpe/comp/cpecomp2_3.py
@@ -262,7 +262,7 @@ def _is_valid_part(self):
             return super(CPEComponent2_3, self)._is_valid_part()
 
         # Compilation of regular expression associated with value of part
-        part_pattern = "^(\{0}|\{1})$".format(self.WILDCARD_ONE,
+        part_pattern = r"^(\{0}|\{1})$".format(self.WILDCARD_ONE,
                                               self.WILDCARD_MULTI)
         part_rxc = re.compile(part_pattern)
 
diff --git a/cpe/comp/cpecomp2_3_uri.py b/cpe/comp/cpecomp2_3_uri.py
index 46480c3..e6ba1b3 100644
--- a/cpe/comp/cpecomp2_3_uri.py
+++ b/cpe/comp/cpecomp2_3_uri.py
@@ -48,7 +48,7 @@ class CPEComponent2_3_URI(CPEComponent2_3):
     # Patterns used to check the value of component
     _PCT_ENCODED = "%21|%22|%23|%24|%25|%26|%27|%28|%29|%2a|%2b|%2c|%2f|%3a|%3b|%3c|%3d|%3e|%3f|%40|%5b|%5c|%5d|%5e|%60|%7b|%7c|%7d|%7e"
     _SPEC_CHRS = "((%01)+|%02)"
-    _UNRESERVED = "[\w\-\.]"
+    _UNRESERVED = r"[\w\-\.]"
 
     #: Separator of components of CPE name with URI style
     SEPARATOR_COMP = ":"
diff --git a/cpe/comp/cpecomp_simple.py b/cpe/comp/cpecomp_simple.py
index ae306ce..c0d1b43 100644
--- a/cpe/comp/cpecomp_simple.py
+++ b/cpe/comp/cpecomp_simple.py
@@ -45,10 +45,10 @@ class CPEComponentSimple(CPEComponent):
     ###############
 
     #: Pattern to check if a character is a alphanumeric or underscore
-    _ALPHANUM_PATTERN = "\w"
+    _ALPHANUM_PATTERN = r"\w"
 
     #: Pattern to check the value of language component of CPE name
-    _LANGTAG_PATTERN = "^([a-z]{2,3}(-([a-z]{2}|[\d]{3}))?)$"
+    _LANGTAG_PATTERN = r"^([a-z]{2,3}(-([a-z]{2}|[\d]{3}))?)$"
 
     #: Pattern to check the value of part component of CPE name
     _PART_PATTERN = "^(h|o|a)$"
diff --git a/tests/unit/test_cpe.py b/tests/unit/test_cpe.py
index 6c323a4..91c5589 100644
--- a/tests/unit/test_cpe.py
+++ b/tests/unit/test_cpe.py
@@ -241,11 +241,11 @@ def test_equals(self):
         the equivalent WFN string.
         """
 
-        self.assertEquals(self.c11, self.c22)
-        self.assertEquals(self.c22, self.c11)
-        self.assertEquals(self.c11, self.c23_wfn)
-        self.assertEquals(self.c11, self.c23_fs)
-        self.assertEquals(self.c23_uri, self.c23_fs)
+        self.assertEqual(self.c11, self.c22)
+        self.assertEqual(self.c22, self.c11)
+        self.assertEqual(self.c11, self.c23_wfn)
+        self.assertEqual(self.c11, self.c23_fs)
+        self.assertEqual(self.c23_uri, self.c23_fs)
     
     @pytest.mark.skip(reason="currently broken")
     def test_incompatible_versions(self):