From 11b1260cf4f00de7bcbd46ec0d85da5e61c12f71 Mon Sep 17 00:00:00 2001
From: Greg Lucas <greg.m.lucas@gmail.com>
Date: Thu, 19 May 2022 11:51:11 -0600
Subject: [PATCH] MNT: Remove dummy_threading because threading is always
 available

With Python 3.7 and above, the threading module is always available.
---
 lib/matplotlib/backends/backend_agg.py | 5 +----
 lib/matplotlib/font_manager.py         | 9 ++-------
 lib/matplotlib/pyplot.py               | 5 +----
 3 files changed, 4 insertions(+), 15 deletions(-)

diff --git a/lib/matplotlib/backends/backend_agg.py b/lib/matplotlib/backends/backend_agg.py
index 1f3e94681372..8fd89c8ef78d 100644
--- a/lib/matplotlib/backends/backend_agg.py
+++ b/lib/matplotlib/backends/backend_agg.py
@@ -21,12 +21,9 @@
 .. _Anti-Grain Geometry: http://agg.sourceforge.net/antigrain.com
 """
 
-try:
-    import threading
-except ImportError:
-    import dummy_threading as threading
 from contextlib import nullcontext
 from math import radians, cos, sin
+import threading
 
 import numpy as np
 
diff --git a/lib/matplotlib/font_manager.py b/lib/matplotlib/font_manager.py
index a94e0ffad9c9..eff1b2362db9 100644
--- a/lib/matplotlib/font_manager.py
+++ b/lib/matplotlib/font_manager.py
@@ -36,12 +36,7 @@
 import re
 import subprocess
 import sys
-try:
-    import threading
-    from threading import Timer
-except ImportError:
-    import dummy_threading as threading
-    from dummy_threading import Timer
+import threading
 
 import matplotlib as mpl
 from matplotlib import _api, _afm, cbook, ft2font, rcParams
@@ -1100,7 +1095,7 @@ def __init__(self, size=None, weight='normal'):
         self.ttflist = []
 
         # Delay the warning by 5s.
-        timer = Timer(5, lambda: _log.warning(
+        timer = threading.Timer(5, lambda: _log.warning(
             'Matplotlib is building the font cache; this may take a moment.'))
         timer.start()
         try:
diff --git a/lib/matplotlib/pyplot.py b/lib/matplotlib/pyplot.py
index 2aedcb5f362a..7a398b25975b 100644
--- a/lib/matplotlib/pyplot.py
+++ b/lib/matplotlib/pyplot.py
@@ -43,11 +43,8 @@
 from numbers import Number
 import re
 import sys
+import threading
 import time
-try:
-    import threading
-except ImportError:
-    import dummy_threading as threading
 
 from cycler import cycler
 import matplotlib