From 3c03942464868c6817a74cd8267b2629e21305f7 Mon Sep 17 00:00:00 2001
From: Serhiy Storchaka <storchaka@gmail.com>
Date: Tue, 29 Mar 2022 23:49:18 +0300
Subject: [PATCH] No longer use undocumented module "sre_constants" (#379)

Closes #378.
---
 pyparsing/core.py    | 7 +++----
 pyparsing/helpers.py | 2 +-
 2 files changed, 4 insertions(+), 5 deletions(-)

diff --git a/pyparsing/core.py b/pyparsing/core.py
index 0d1ca6fb..bac41127 100644
--- a/pyparsing/core.py
+++ b/pyparsing/core.py
@@ -23,7 +23,6 @@
 import copy
 import warnings
 import re
-import sre_constants
 import sys
 from collections.abc import Iterable
 import traceback
@@ -2783,7 +2782,7 @@ def __init__(
 
             try:
                 self.re = re.compile(self.reString)
-            except sre_constants.error:
+            except re.error:
                 self.re = None
             else:
                 self.re_match = self.re.match
@@ -2966,7 +2965,7 @@ def re(self):
         else:
             try:
                 return re.compile(self.pattern, self.flags)
-            except sre_constants.error:
+            except re.error:
                 raise ValueError(
                     "invalid pattern ({!r}) passed to Regex".format(self.pattern)
                 )
@@ -3188,7 +3187,7 @@ def __init__(
             self.re = re.compile(self.pattern, self.flags)
             self.reString = self.pattern
             self.re_match = self.re.match
-        except sre_constants.error:
+        except re.error:
             raise ValueError(
                 "invalid pattern {!r} passed to Regex".format(self.pattern)
             )
diff --git a/pyparsing/helpers.py b/pyparsing/helpers.py
index 799de749..be8a3657 100644
--- a/pyparsing/helpers.py
+++ b/pyparsing/helpers.py
@@ -312,7 +312,7 @@ def one_of(
 
             return ret
 
-        except sre_constants.error:
+        except re.error:
             warnings.warn(
                 "Exception creating Regex for one_of, building MatchFirst", stacklevel=2
             )