diff --git a/jsonmodels/utilities.py b/jsonmodels/utilities.py
index 0e18eb8..811bd70 100644
--- a/jsonmodels/utilities.py
+++ b/jsonmodels/utilities.py
@@ -1,5 +1,4 @@
 import re
-import sre_constants
 from collections import namedtuple
 
 SCALAR_TYPES = tuple(list((str,)) + [int, float, bool])
@@ -97,10 +96,10 @@ def is_ecma_regex(regex):
 
     try:
         re.compile(regex)
-    except sre_constants.error as err:
+    except re.error as err:
         raise ValueError(
             f"Given regex {regex} isn't ECMA regex nor Python regex: {err}."
-        )
+        ) from err
     return False
 
 
diff --git a/tests/test_project.py b/tests/test_project.py
index 12e4b9e..cd54547 100644
--- a/tests/test_project.py
+++ b/tests/test_project.py
@@ -26,7 +26,7 @@ def test_pep8_and_complexity():
     not tests.LINT or not tests.CHECK_SPELLING, reason="No spelling check."
 )
 def test_docs():
-    run("sphinx-build -b spelling -d docs/_build/doctress " "docs docs/build/spelling")
+    run("sphinx-build -b spelling -d docs/_build/doctress docs docs/build/spelling")
 
 
 def _collect_static(dirs):