Try updating scons version.

requirements.in

@@ -1,6 +1,6 @@
 pip-tools~=6.0.1
 black~=20.8b1
-scons~=3.1
+scons~=4.5
 cython~=0.29.21
 autopxd2~=1.1.0
 pycparser~=2.20

requirements.txt

@@ -185,9 +185,9 @@ regex==2021.4.4 \
     --hash=sha256:fa4537fb4a98fe8fde99626e4681cc644bdcf2a795038533f9f711513a862ae6 \
     --hash=sha256:fd45ff9293d9274c5008a2054ecef86a9bfe819a67c7be1afb65e69b405b3042
     # via black
-scons==3.1.2 \
-    --hash=sha256:0f860678cd96fc943ff2294389b0f33cbe51080801591497bc652e72237f0176 \
-    --hash=sha256:8aaa483c303efeb678e6f7c776c8444a482f8ddc3ad891f8b6cdd35264da9a1f
+scons==4.5.2 \
+    --hash=sha256:2f66a1c5c485068a496c12356583eefb2d79e17177278c7334b12b460f0503ce \
+    --hash=sha256:813360b2bce476bc9cc12a0f3a22d46ce520796b352557202cb07d3e402f5458
     # via -r requirements.in
 six==1.15.0 \
     --hash=sha256:30639c035cdb23534cd4aa2dd52c3bf48f06e5f4a941509c8bafd8ce11080259 \
@@ -300,3 +300,7 @@ pip==21.1 \
     --hash=sha256:a810bf07c3723a28621c29abe8e34429fa082c337f89aea9a795865416b66d3e \
     --hash=sha256:ea9f2668484893e90149fd5a6124e04651ffedd67203a8aaf030d31406b937a4
     # via pip-tools
+setuptools==68.0.0 \
+    --hash=sha256:11e52c67415a381d10d6b462ced9cfb97066179f0e871399e006c4ab101fc85f \
+    --hash=sha256:baf1fdb41c6da4cd2eae722e135500da913332ab3f2f5c7d33af9b492acb5235
+    # via scons