Index: lang/python310/Makefile
===================================================================
--- lang/python310/Makefile
+++ lang/python310/Makefile
@@ -1,6 +1,6 @@
 PORTNAME=	python
 DISTVERSION=	${PYTHON_DISTVERSION}
-PORTREVISION=	2
+PORTREVISION=	3
 CATEGORIES=	lang python
 MASTER_SITES=	PYTHON/ftp/python/${DISTVERSION:C/[a-z].*//}
 PKGNAMESUFFIX=	${PYTHON_SUFFIX}
@@ -16,7 +16,7 @@
 LIB_DEPENDS=	libffi.so:devel/libffi
 
 USES=		compiler:c11 cpe ncurses pathfix pkgconfig \
-		python:${PYTHON_DISTVERSION:R},env readline shebangfix ssl tar:xz
+		python:${PYTHON_DISTVERSION:R},env readline shebangfix ssl tar:xz trigger
 PATHFIX_MAKEFILEIN=	Makefile.pre.in
 USE_LDCONFIG=	yes
 GNU_CONFIGURE=	yes
@@ -25,6 +25,7 @@
 SHEBANG_FILES+=	Lib/test/ziptestdata/exe_with_z64 \
 		Lib/test/ziptestdata/exe_with_zip \
 		Lib/test/ziptestdata/header.sh
+TRIGGERS=	${PYTHON_VERSION}
 
 DISABLED_EXTENSIONS=	_sqlite3 _tkinter _gdbm
 CONFIGURE_ARGS+=	--enable-shared --without-ensurepip \
Index: lang/python310/files/python3.10.ucl.in
===================================================================
--- /dev/null
+++ lang/python310/files/python3.10.ucl.in
@@ -0,0 +1,64 @@
+path_glob: "%%PYTHON_SITELIBDIR%%/*"
+cleanup: {
+	type: lua
+	sandbox: false
+	script: <<EOS
+function cleanup(directory)
+  for _,d in ipairs(pkg.readdir(directory)) do
+    local full_path = directory .. "/" .. d
+    local stat = pkg.stat(full_path)
+    if stat["type"] == "dir" then
+      cleanup(full_path)
+    end
+    os.remove(full_path)
+  end
+  os.remove(directory)
+end
+
+cleanup("%%PYTHON_LIBDIR%%")
+EOS
+}
+
+trigger: {
+	type: lua
+	sandbox: false
+	script: <<EOS
+function cleanup(directory)
+  for _,d in ipairs(pkg.readdir(directory)) do
+    local full_path = directory .. "/" .. d
+    local stat = pkg.stat(full_path)
+    if stat["type"] == "dir" then
+      if (d ~= "__pycache__") then
+        cleanup(full_path)
+      else
+        for _,bytecode_file in ipairs(pkg.readdir(full_path)) do
+          local file_origin = string.gsub(bytecode_file, "[.]cpython[-]%%PYTHON_SUFFIX%%[.].*pyc", ".py")
+          if file_origin  then
+            local origin_path = directory .. "/" .. file_origin
+            if (not pkg.stat(origin_path)) then
+              --print(">=> removed stale bytecode " .. bytecode_file)
+              os.remove(full_path .. "/" .. bytecode_file)
+            end
+          end
+        end
+      end
+      local res = pkg.readdir(full_path)
+      -- to appease out-of-order execution in package building environments
+      if res == nil then
+        break
+      end
+      if #res == 0 then
+        --print(">=> removed empty directory " .. full_path )
+        os.remove(full_path)
+      end
+    end
+  end
+end
+
+print("Cleaning stale bytecode files...")
+cleanup("%%PYTHON_SITELIBDIR%%")
+
+print("Byte-compiling Python source files...")
+pkg.exec({"%%PYTHON_VERSION%%", "-m", "compileall", "-q", "-o", "0", "-o", "1", "-o", "2", "%%PYTHON_SITELIBDIR%%"})
+EOS
+}
Index: lang/python311/Makefile
===================================================================
--- lang/python311/Makefile
+++ lang/python311/Makefile
@@ -1,6 +1,6 @@
 PORTNAME=	python
 DISTVERSION=	${PYTHON_DISTVERSION}
-PORTREVISION=	2
+PORTREVISION=	3
 CATEGORIES=	lang python
 MASTER_SITES=	PYTHON/ftp/python/${DISTVERSION:C/[a-z].*//}
 PKGNAMESUFFIX=	${PYTHON_SUFFIX}
@@ -16,7 +16,7 @@
 LIB_DEPENDS=	libffi.so:devel/libffi
 
 USES=		compiler:c11 cpe ncurses pathfix pkgconfig \
-		python:${PYTHON_DISTVERSION:R},env readline shebangfix ssl tar:xz
+		python:${PYTHON_DISTVERSION:R},env readline shebangfix ssl tar:xz trigger
 PATHFIX_MAKEFILEIN=	Makefile.pre.in
 USE_LDCONFIG=	yes
 GNU_CONFIGURE=	yes
@@ -25,6 +25,7 @@
 SHEBANG_FILES+=	Lib/test/ziptestdata/exe_with_z64 \
 		Lib/test/ziptestdata/exe_with_zip \
 		Lib/test/ziptestdata/header.sh
+TRIGGER=	${PYTHON_VERSION}
 
 DISABLED_EXTENSIONS=	_sqlite3 _tkinter _gdbm
 CONFIGURE_ARGS+=	--enable-shared --without-ensurepip \
Index: lang/python311/files/python3.11.ucl.in
===================================================================
--- /dev/null
+++ lang/python311/files/python3.11.ucl.in
@@ -0,0 +1,64 @@
+path_glob: "%%PYTHON_SITELIBDIR%%/*"
+cleanup: {
+	type: lua
+	sandbox: false
+	script: <<EOS
+function cleanup(directory)
+  for _,d in ipairs(pkg.readdir(directory)) do
+    local full_path = directory .. "/" .. d
+    local stat = pkg.stat(full_path)
+    if stat["type"] == "dir" then
+      cleanup(full_path)
+    end
+    os.remove(full_path)
+  end
+  os.remove(directory)
+end
+
+cleanup("%%PYTHON_LIBDIR%%")
+EOS
+}
+
+trigger: {
+	type: lua
+	sandbox: false
+	script: <<EOS
+function cleanup(directory)
+  for _,d in ipairs(pkg.readdir(directory)) do
+    local full_path = directory .. "/" .. d
+    local stat = pkg.stat(full_path)
+    if stat["type"] == "dir" then
+      if (d ~= "__pycache__") then
+        cleanup(full_path)
+      else
+        for _,bytecode_file in ipairs(pkg.readdir(full_path)) do
+          local file_origin = string.gsub(bytecode_file, "[.]cpython[-]%%PYTHON_SUFFIX%%[.].*pyc", ".py")
+          if file_origin  then
+            local origin_path = directory .. "/" .. file_origin
+            if (not pkg.stat(origin_path)) then
+              --print(">=> removed stale bytecode " .. bytecode_file)
+              os.remove(full_path .. "/" .. bytecode_file)
+            end
+          end
+        end
+      end
+      local res = pkg.readdir(full_path)
+      -- to appease out-of-order execution in package building environments
+      if res == nil then
+        break
+      end
+      if #res == 0 then
+        --print(">=> removed empty directory " .. full_path )
+        os.remove(full_path)
+      end
+    end
+  end
+end
+
+print("Cleaning stale bytecode files...")
+cleanup("%%PYTHON_SITELIBDIR%%")
+
+print("Byte-compiling Python source files...")
+pkg.exec({"%%PYTHON_VERSION%%", "-m", "compileall", "-q", "-o", "0", "-o", "1", "-o", "2", "%%PYTHON_SITELIBDIR%%"})
+EOS
+}
Index: lang/python37/Makefile
===================================================================
--- lang/python37/Makefile
+++ lang/python37/Makefile
@@ -20,12 +20,13 @@
 		libmpdec.so:math/mpdecimal
 
 USES=		cpe ncurses pathfix pkgconfig python:${PYTHON_DISTVERSION:R},env readline \
-		shebangfix ssl tar:xz
+		shebangfix ssl tar:xz trigger
 PATHFIX_MAKEFILEIN=	Makefile.pre.in
 USE_LDCONFIG=	yes
 GNU_CONFIGURE=	yes
 python_CMD=	${PREFIX}/bin/python${PYTHON_DISTVERSION:R}
 SHEBANG_FILES=	Lib/*.py Lib/*/*.py Lib/*/*/*.py Lib/*/*/*/*.py
+TRIGGERS=	${PYTHON_VERSION}
 
 DISABLED_EXTENSIONS=	_sqlite3 _tkinter _gdbm
 CONFIGURE_ARGS+=	--enable-shared --with-system-ffi --with-system-libmpdec --without-ensurepip
Index: lang/python37/files/python3.7.ucl.in
===================================================================
--- /dev/null
+++ lang/python37/files/python3.7.ucl.in
@@ -0,0 +1,66 @@
+path_glob: "%%PYTHON_SITELIBDIR%%/*"
+cleanup: {
+	type: lua
+	sandbox: false
+	script: <<EOS
+function cleanup(directory)
+  for _,d in ipairs(pkg.readdir(directory)) do
+    local full_path = directory .. "/" .. d
+    local stat = pkg.stat(full_path)
+    if stat["type"] == "dir" then
+      cleanup(full_path)
+    end
+    os.remove(full_path)
+  end
+  os.remove(directory)
+end
+
+cleanup("%%PYTHON_LIBDIR%%")
+EOS
+}
+
+trigger: {
+	type: lua
+	sandbox: false
+	script: <<EOS
+function cleanup(directory)
+  for _,d in ipairs(pkg.readdir(directory)) do
+    local full_path = directory .. "/" .. d
+    local stat = pkg.stat(full_path)
+    if stat["type"] == "dir" then
+      if (d ~= "__pycache__") then
+        cleanup(full_path)
+      else
+        for _,bytecode_file in ipairs(pkg.readdir(full_path)) do
+          local file_origin = string.gsub(bytecode_file, "[.]cpython[-]%%PYTHON_SUFFIX%%[.].*pyc", ".py")
+          if file_origin  then
+            local origin_path = directory .. "/" .. file_origin
+            if (not pkg.stat(origin_path)) then
+              --print(">=> removed stale bytecode " .. bytecode_file)
+              os.remove(full_path .. "/" .. bytecode_file)
+            end
+          end
+        end
+      end
+      local res = pkg.readdir(full_path)
+      -- to appease out-of-order execution in package building environments
+      if res == nil then
+        break
+      end
+      if #res == 0 then
+        --print(">=> removed empty directory " .. full_path )
+        os.remove(full_path)
+      end
+    end
+  end
+end
+
+print("Cleaning stale bytecode files...")
+cleanup("%%PYTHON_SITELIBDIR%%")
+
+print("Byte-compiling Python source files...")
+pkg.exec({"%%PYTHON_VERSION%%", "-m", "compileall", "-q", "%%PYTHON_SITELIBDIR%%"})
+pkg.exec({"%%PYTHON_VERSION%%", "-O", "-m", "compileall", "-q", "%%PYTHON_SITELIBDIR%%"})
+pkg.exec({"%%PYTHON_VERSION%%", "-OO", "-m", "compileall", "-q", "%%PYTHON_SITELIBDIR%%"})
+EOS
+}
Index: lang/python38/Makefile
===================================================================
--- lang/python38/Makefile
+++ lang/python38/Makefile
@@ -1,6 +1,6 @@
 PORTNAME=	python
 DISTVERSION=	${PYTHON_DISTVERSION}
-PORTREVISION=	2
+PORTREVISION=	3
 CATEGORIES=	lang python
 MASTER_SITES=	PYTHON/ftp/python/${DISTVERSION}
 PKGNAMESUFFIX=	${PYTHON_SUFFIX}
@@ -16,7 +16,7 @@
 LIB_DEPENDS=	libffi.so:devel/libffi
 
 USES=		cpe ncurses pathfix pkgconfig python:${PYTHON_DISTVERSION:R},env readline \
-		shebangfix ssl tar:xz
+		shebangfix ssl tar:xz trigger
 PATHFIX_MAKEFILEIN=	Makefile.pre.in
 USE_LDCONFIG=	yes
 GNU_CONFIGURE=	yes
@@ -25,6 +25,7 @@
 SHEBANG_FILES+=	Lib/test/ziptestdata/exe_with_z64 \
 		Lib/test/ziptestdata/exe_with_zip \
 		Lib/test/ziptestdata/header.sh
+TRIGGERS=	${PYTHON_VERSION}
 
 DISABLED_EXTENSIONS=	_sqlite3 _tkinter _gdbm
 CONFIGURE_ARGS+=	--enable-shared --without-ensurepip \
Index: lang/python38/files/python3.8.ucl.in
===================================================================
--- /dev/null
+++ lang/python38/files/python3.8.ucl.in
@@ -0,0 +1,66 @@
+path_glob: "%%PYTHON_SITELIBDIR%%/*"
+cleanup: {
+	type: lua
+	sandbox: false
+	script: <<EOS
+function cleanup(directory)
+  for _,d in ipairs(pkg.readdir(directory)) do
+    local full_path = directory .. "/" .. d
+    local stat = pkg.stat(full_path)
+    if stat["type"] == "dir" then
+      cleanup(full_path)
+    end
+    os.remove(full_path)
+  end
+  os.remove(directory)
+end
+
+cleanup("%%PYTHON_LIBDIR%%")
+EOS
+}
+
+trigger: {
+	type: lua
+	sandbox: false
+	script: <<EOS
+function cleanup(directory)
+  for _,d in ipairs(pkg.readdir(directory)) do
+    local full_path = directory .. "/" .. d
+    local stat = pkg.stat(full_path)
+    if stat["type"] == "dir" then
+      if (d ~= "__pycache__") then
+        cleanup(full_path)
+      else
+        for _,bytecode_file in ipairs(pkg.readdir(full_path)) do
+          local file_origin = string.gsub(bytecode_file, "[.]cpython[-]%%PYTHON_SUFFIX%%[.].*pyc", ".py")
+          if file_origin  then
+            local origin_path = directory .. "/" .. file_origin
+            if (not pkg.stat(origin_path)) then
+              --print(">=> removed stale bytecode " .. bytecode_file)
+              os.remove(full_path .. "/" .. bytecode_file)
+            end
+          end
+        end
+      end
+      local res = pkg.readdir(full_path)
+      -- to appease out-of-order execution in package building environments
+      if res == nil then
+        break
+      end
+      if #res == 0 then
+        --print(">=> removed empty directory " .. full_path )
+        os.remove(full_path)
+      end
+    end
+  end
+end
+
+print("Cleaning stale bytecode files...")
+cleanup("%%PYTHON_SITELIBDIR%%")
+
+print("Byte-compiling Python source files...")
+pkg.exec({"%%PYTHON_VERSION%%", "-m", "compileall", "-q", "%%PYTHON_SITELIBDIR%%"})
+pkg.exec({"%%PYTHON_VERSION%%", "-O", "-m", "compileall", "-q", "%%PYTHON_SITELIBDIR%%"})
+pkg.exec({"%%PYTHON_VERSION%%", "-OO", "-m", "compileall", "-q", "%%PYTHON_SITELIBDIR%%"})
+EOS
+}
Index: lang/python39/Makefile
===================================================================
--- lang/python39/Makefile
+++ lang/python39/Makefile
@@ -1,6 +1,6 @@
 PORTNAME=	python
 DISTVERSION=	${PYTHON_DISTVERSION}
-PORTREVISION=	2
+PORTREVISION=	3
 CATEGORIES=	lang python
 MASTER_SITES=	PYTHON/ftp/python/${DISTVERSION}
 PKGNAMESUFFIX=	${PYTHON_SUFFIX}
@@ -16,7 +16,7 @@
 LIB_DEPENDS=	libffi.so:devel/libffi
 
 USES=		compiler:c11 cpe ncurses pathfix pkgconfig \
-		python:${PYTHON_DISTVERSION:R},env readline shebangfix ssl tar:xz
+		python:${PYTHON_DISTVERSION:R},env readline shebangfix ssl tar:xz trigger
 PATHFIX_MAKEFILEIN=	Makefile.pre.in
 USE_LDCONFIG=	yes
 GNU_CONFIGURE=	yes
@@ -25,6 +25,7 @@
 SHEBANG_FILES+=	Lib/test/ziptestdata/exe_with_z64 \
 		Lib/test/ziptestdata/exe_with_zip \
 		Lib/test/ziptestdata/header.sh
+TRIGGERS=	${PYTHON_VERSION}
 
 DISABLED_EXTENSIONS=	_sqlite3 _tkinter _gdbm
 CONFIGURE_ARGS+=	--enable-shared --without-ensurepip \
Index: lang/python39/files/python3.9.ucl.in
===================================================================
--- /dev/null
+++ lang/python39/files/python3.9.ucl.in
@@ -0,0 +1,64 @@
+path_glob: "%%PYTHON_SITELIBDIR%%/*"
+cleanup: {
+	type: lua
+	sandbox: false
+	script: <<EOS
+function cleanup(directory)
+  for _,d in ipairs(pkg.readdir(directory)) do
+    local full_path = directory .. "/" .. d
+    local stat = pkg.stat(full_path)
+    if stat["type"] == "dir" then
+      cleanup(full_path)
+    end
+    os.remove(full_path)
+  end
+  os.remove(directory)
+end
+
+cleanup("%%PYTHON_LIBDIR%%")
+EOS
+}
+
+trigger: {
+	type: lua
+	sandbox: false
+	script: <<EOS
+function cleanup(directory)
+  for _,d in ipairs(pkg.readdir(directory)) do
+    local full_path = directory .. "/" .. d
+    local stat = pkg.stat(full_path)
+    if stat["type"] == "dir" then
+      if (d ~= "__pycache__") then
+        cleanup(full_path)
+      else
+        for _,bytecode_file in ipairs(pkg.readdir(full_path)) do
+          local file_origin = string.gsub(bytecode_file, "[.]cpython[-]%%PYTHON_SUFFIX%%[.].*pyc", ".py")
+          if file_origin  then
+            local origin_path = directory .. "/" .. file_origin
+            if (not pkg.stat(origin_path)) then
+              --print(">=> removed stale bytecode " .. bytecode_file)
+              os.remove(full_path .. "/" .. bytecode_file)
+            end
+          end
+        end
+      end
+      local res = pkg.readdir(full_path)
+      -- to appease out-of-order execution in package building environments
+      if res == nil then
+        break
+      end
+      if #res == 0 then
+        --print(">=> removed empty directory " .. full_path )
+        os.remove(full_path)
+      end
+    end
+  end
+end
+
+print("Cleaning stale bytecode files...")
+cleanup("%%PYTHON_SITELIBDIR%%")
+
+print("Byte-compiling Python source files...")
+pkg.exec({"%%PYTHON_VERSION%%", "-m", "compileall", "-q", "-o", "0", "-o", "1", "-o", "2", "%%PYTHON_SITELIBDIR%%"})
+EOS
+}