diff --git a/3.11-minimal/test/run-pytest b/3.11-minimal/test/run-pytest
index e69959ad..9810fe89 100755
--- a/3.11-minimal/test/run-pytest
+++ b/3.11-minimal/test/run-pytest
@@ -8,8 +8,9 @@
 
 THISDIR=$(dirname ${BASH_SOURCE[0]})
 
-PYTHON_VERSION="3.12"
-if [[ ! -f "/usr/bin/python$PYTHON_VERSION" ]]; then
-  PYTHON_VERSION="3.13"
+if python3 -c 'import sys; sys.exit(0 if sys.version_info < (3,13) else 1)'; then
+  PYTHON_VERSION="3.12"
+else
+  PYTHON_VERSION="3"
 fi
 cd "${THISDIR}" && "python${PYTHON_VERSION}" -m pytest -s -rA --showlocals -vv test_container_*.py
diff --git a/3.11/test/run-pytest b/3.11/test/run-pytest
index e69959ad..9810fe89 100755
--- a/3.11/test/run-pytest
+++ b/3.11/test/run-pytest
@@ -8,8 +8,9 @@
 
 THISDIR=$(dirname ${BASH_SOURCE[0]})
 
-PYTHON_VERSION="3.12"
-if [[ ! -f "/usr/bin/python$PYTHON_VERSION" ]]; then
-  PYTHON_VERSION="3.13"
+if python3 -c 'import sys; sys.exit(0 if sys.version_info < (3,13) else 1)'; then
+  PYTHON_VERSION="3.12"
+else
+  PYTHON_VERSION="3"
 fi
 cd "${THISDIR}" && "python${PYTHON_VERSION}" -m pytest -s -rA --showlocals -vv test_container_*.py
diff --git a/3.12-minimal/test/run-pytest b/3.12-minimal/test/run-pytest
index e69959ad..9810fe89 100755
--- a/3.12-minimal/test/run-pytest
+++ b/3.12-minimal/test/run-pytest
@@ -8,8 +8,9 @@
 
 THISDIR=$(dirname ${BASH_SOURCE[0]})
 
-PYTHON_VERSION="3.12"
-if [[ ! -f "/usr/bin/python$PYTHON_VERSION" ]]; then
-  PYTHON_VERSION="3.13"
+if python3 -c 'import sys; sys.exit(0 if sys.version_info < (3,13) else 1)'; then
+  PYTHON_VERSION="3.12"
+else
+  PYTHON_VERSION="3"
 fi
 cd "${THISDIR}" && "python${PYTHON_VERSION}" -m pytest -s -rA --showlocals -vv test_container_*.py
diff --git a/3.12/test/run-pytest b/3.12/test/run-pytest
index e69959ad..9810fe89 100755
--- a/3.12/test/run-pytest
+++ b/3.12/test/run-pytest
@@ -8,8 +8,9 @@
 
 THISDIR=$(dirname ${BASH_SOURCE[0]})
 
-PYTHON_VERSION="3.12"
-if [[ ! -f "/usr/bin/python$PYTHON_VERSION" ]]; then
-  PYTHON_VERSION="3.13"
+if python3 -c 'import sys; sys.exit(0 if sys.version_info < (3,13) else 1)'; then
+  PYTHON_VERSION="3.12"
+else
+  PYTHON_VERSION="3"
 fi
 cd "${THISDIR}" && "python${PYTHON_VERSION}" -m pytest -s -rA --showlocals -vv test_container_*.py
diff --git a/3.13-minimal/test/run-pytest b/3.13-minimal/test/run-pytest
index e69959ad..9810fe89 100755
--- a/3.13-minimal/test/run-pytest
+++ b/3.13-minimal/test/run-pytest
@@ -8,8 +8,9 @@
 
 THISDIR=$(dirname ${BASH_SOURCE[0]})
 
-PYTHON_VERSION="3.12"
-if [[ ! -f "/usr/bin/python$PYTHON_VERSION" ]]; then
-  PYTHON_VERSION="3.13"
+if python3 -c 'import sys; sys.exit(0 if sys.version_info < (3,13) else 1)'; then
+  PYTHON_VERSION="3.12"
+else
+  PYTHON_VERSION="3"
 fi
 cd "${THISDIR}" && "python${PYTHON_VERSION}" -m pytest -s -rA --showlocals -vv test_container_*.py
diff --git a/3.13/test/run-pytest b/3.13/test/run-pytest
index e69959ad..9810fe89 100755
--- a/3.13/test/run-pytest
+++ b/3.13/test/run-pytest
@@ -8,8 +8,9 @@
 
 THISDIR=$(dirname ${BASH_SOURCE[0]})
 
-PYTHON_VERSION="3.12"
-if [[ ! -f "/usr/bin/python$PYTHON_VERSION" ]]; then
-  PYTHON_VERSION="3.13"
+if python3 -c 'import sys; sys.exit(0 if sys.version_info < (3,13) else 1)'; then
+  PYTHON_VERSION="3.12"
+else
+  PYTHON_VERSION="3"
 fi
 cd "${THISDIR}" && "python${PYTHON_VERSION}" -m pytest -s -rA --showlocals -vv test_container_*.py
diff --git a/3.6/test/run-pytest b/3.6/test/run-pytest
index e69959ad..9810fe89 100755
--- a/3.6/test/run-pytest
+++ b/3.6/test/run-pytest
@@ -8,8 +8,9 @@
 
 THISDIR=$(dirname ${BASH_SOURCE[0]})
 
-PYTHON_VERSION="3.12"
-if [[ ! -f "/usr/bin/python$PYTHON_VERSION" ]]; then
-  PYTHON_VERSION="3.13"
+if python3 -c 'import sys; sys.exit(0 if sys.version_info < (3,13) else 1)'; then
+  PYTHON_VERSION="3.12"
+else
+  PYTHON_VERSION="3"
 fi
 cd "${THISDIR}" && "python${PYTHON_VERSION}" -m pytest -s -rA --showlocals -vv test_container_*.py
diff --git a/3.9-minimal/test/run-pytest b/3.9-minimal/test/run-pytest
index e69959ad..9810fe89 100755
--- a/3.9-minimal/test/run-pytest
+++ b/3.9-minimal/test/run-pytest
@@ -8,8 +8,9 @@
 
 THISDIR=$(dirname ${BASH_SOURCE[0]})
 
-PYTHON_VERSION="3.12"
-if [[ ! -f "/usr/bin/python$PYTHON_VERSION" ]]; then
-  PYTHON_VERSION="3.13"
+if python3 -c 'import sys; sys.exit(0 if sys.version_info < (3,13) else 1)'; then
+  PYTHON_VERSION="3.12"
+else
+  PYTHON_VERSION="3"
 fi
 cd "${THISDIR}" && "python${PYTHON_VERSION}" -m pytest -s -rA --showlocals -vv test_container_*.py
diff --git a/3.9/test/run-pytest b/3.9/test/run-pytest
index e69959ad..9810fe89 100755
--- a/3.9/test/run-pytest
+++ b/3.9/test/run-pytest
@@ -8,8 +8,9 @@
 
 THISDIR=$(dirname ${BASH_SOURCE[0]})
 
-PYTHON_VERSION="3.12"
-if [[ ! -f "/usr/bin/python$PYTHON_VERSION" ]]; then
-  PYTHON_VERSION="3.13"
+if python3 -c 'import sys; sys.exit(0 if sys.version_info < (3,13) else 1)'; then
+  PYTHON_VERSION="3.12"
+else
+  PYTHON_VERSION="3"
 fi
 cd "${THISDIR}" && "python${PYTHON_VERSION}" -m pytest -s -rA --showlocals -vv test_container_*.py
diff --git a/test/run-pytest b/test/run-pytest
index e69959ad..9810fe89 100755
--- a/test/run-pytest
+++ b/test/run-pytest
@@ -8,8 +8,9 @@
 
 THISDIR=$(dirname ${BASH_SOURCE[0]})
 
-PYTHON_VERSION="3.12"
-if [[ ! -f "/usr/bin/python$PYTHON_VERSION" ]]; then
-  PYTHON_VERSION="3.13"
+if python3 -c 'import sys; sys.exit(0 if sys.version_info < (3,13) else 1)'; then
+  PYTHON_VERSION="3.12"
+else
+  PYTHON_VERSION="3"
 fi
 cd "${THISDIR}" && "python${PYTHON_VERSION}" -m pytest -s -rA --showlocals -vv test_container_*.py