Index: Mk/Uses/python.mk
===================================================================
--- Mk/Uses/python.mk
+++ Mk/Uses/python.mk
@@ -334,6 +334,10 @@
 
 _PYTHON_VERSION:=	${PYTHON_DEFAULT}
 
+.if empty(_PYTHON_ARGS)
+_PYTHON_ARGS=	3.6+
+.endif
+
 # Validate Python version whether it meets the version restriction.
 _PYTHON_VERSION_CHECK:=		${_PYTHON_ARGS:C/^([1-9]\.[0-9])$/\1-\1/}
 _PYTHON_VERSION_MINIMUM_TMP:=	${_PYTHON_VERSION_CHECK:C/([1-9]\.[0-9])[-+].*/\1/}
Index: converters/py-webencodings/Makefile
===================================================================
--- converters/py-webencodings/Makefile
+++ converters/py-webencodings/Makefile
@@ -11,7 +11,7 @@
 
 LICENSE=	BSD3CLAUSE
 
-USES=		python
+USES=		python:2.7+
 USE_PYTHON=	distutils autoplist
 NO_ARCH=	yes
 
Index: databases/py-sqlite3/Makefile
===================================================================
--- databases/py-sqlite3/Makefile
+++ databases/py-sqlite3/Makefile
@@ -20,7 +20,7 @@
 
 PORTSCOUT=	ignore:1
 
-USES=		compiler:c11 python tar:xz
+USES=		compiler:c11 python:2.7+ tar:xz
 USE_PYTHON=	autoplist distutils allflavors
 
 DISTINFO_FILE=	${PORTSDIR}/lang/python${PYTHON_SUFFIX}/distinfo
Index: devel/py-Jinja2/Makefile
===================================================================
--- devel/py-Jinja2/Makefile
+++ devel/py-Jinja2/Makefile
@@ -20,7 +20,7 @@
 
 NO_ARCH=	yes
 .if empty(PKGNAMESUFFIX)
-USES=		python
+USES=		python:2.7+
 USE_PYTHON=	autoplist distutils
 .endif
 .if ${PKGNAMESUFFIX} == -doc
Index: devel/py-babel/Makefile
===================================================================
--- devel/py-babel/Makefile
+++ devel/py-babel/Makefile
@@ -15,7 +15,7 @@
 
 RUN_DEPENDS=	${PYTHON_PKGNAMEPREFIX}pytz>0:devel/py-pytz@${PY_FLAVOR}
 
-USES=		python
+USES=		python:2.7+
 USE_PYTHON=	autoplist concurrent distutils
 
 NO_ARCH=	yes
Index: devel/py-future/Makefile
===================================================================
--- devel/py-future/Makefile
+++ devel/py-future/Makefile
@@ -13,7 +13,7 @@
 LICENSE=	MIT
 LICENSE_FILE=	${WRKSRC}/LICENSE.txt
 
-USES=		python
+USES=		python:2.7+
 USE_PYTHON=	autoplist concurrent distutils
 
 NO_ARCH=	yes
Index: devel/py-game_sdl2/Makefile
===================================================================
--- devel/py-game_sdl2/Makefile
+++ devel/py-game_sdl2/Makefile
@@ -19,7 +19,7 @@
 # Upstream tends to reroll distfiles before moving under /release/
 PORTSCOUT=	site:http://www.renpy.org/dl/release/
 
-USES=		jpeg python sdl
+USES=		jpeg python:2.7+ sdl
 USE_SDL=	image2 mixer2 ttf2
 USE_PYTHON=	autoplist distutils cython
 EXCLUDE=	gen gen3 PKG-INFO '*.egg-info'
Index: devel/py-ply/Makefile
===================================================================
--- devel/py-ply/Makefile
+++ devel/py-ply/Makefile
@@ -12,7 +12,7 @@
 
 LICENSE=	BSD3CLAUSE
 
-USES=		python
+USES=		python:2.7+
 USES+=		shebangfix
 USE_PYTHON=	autoplist concurrent distutils
 NO_ARCH=	yes
Index: devel/py-pycparser/Makefile
===================================================================
--- devel/py-pycparser/Makefile
+++ devel/py-pycparser/Makefile
@@ -13,7 +13,7 @@
 LICENSE=	BSD3CLAUSE
 LICENSE_FILE=	${WRKSRC}/LICENSE
 
-USES=		python
+USES=		python:2.7+
 USE_PYTHON=	autoplist concurrent distutils
 
 NO_ARCH=	yes
Index: devel/py-pytz/Makefile
===================================================================
--- devel/py-pytz/Makefile
+++ devel/py-pytz/Makefile
@@ -14,7 +14,7 @@
 LICENSE=	MIT
 LICENSE_FILE=	${WRKSRC}/LICENSE.txt
 
-USES=		python
+USES=		python:2.7+
 USE_PYTHON=	autoplist distutils
 
 NO_ARCH=	yes
Index: devel/py-setuptools/Makefile
===================================================================
--- devel/py-setuptools/Makefile
+++ devel/py-setuptools/Makefile
@@ -17,7 +17,7 @@
 LICENSE_FILE=	${WRKSRC}/LICENSE
 
 NO_ARCH=	yes
-USES=		python zip
+USES=		python:2.7+ zip
 USE_PYTHON=	allflavors autoplist concurrent distutils
 
 PYDISTUTILS_SETUP=	${PYSETUP}
Index: devel/py-setuptools_scm/Makefile
===================================================================
--- devel/py-setuptools_scm/Makefile
+++ devel/py-setuptools_scm/Makefile
@@ -18,7 +18,7 @@
 		git:devel/git \
 		${PY_MERCURIAL}
 
-USES=		python
+USES=		python:2.7+
 USE_PYTHON=	autoplist distutils
 
 NO_ARCH=	yes
Index: devel/py-six/Makefile
===================================================================
--- devel/py-six/Makefile
+++ devel/py-six/Makefile
@@ -15,7 +15,7 @@
 
 TEST_DEPENDS=	${PYTHON_PKGNAMEPREFIX}pytest>0:devel/py-pytest@${PY_FLAVOR}
 
-USES=		python
+USES=		python:2.7+
 USE_PYTHON=	autoplist concurrent distutils
 
 NO_ARCH=	yes
Index: devel/py-subversion/Makefile
===================================================================
--- devel/py-subversion/Makefile
+++ devel/py-subversion/Makefile
@@ -9,7 +9,7 @@
 
 BUILD_DEPENDS=	${LOCALBASE}/include/py3c.h:devel/py3c
 
-USES=		python
+USES=		python:2.7+
 USE_PYTHON=	flavors py3kplist
 
 PORTREVISION_114=	0
Index: devel/scons/Makefile
===================================================================
--- devel/scons/Makefile
+++ devel/scons/Makefile
@@ -15,7 +15,7 @@
 
 RUN_DEPENDS=	gm4:devel/m4
 
-USES=		python shebangfix
+USES=		python:2.7+ shebangfix
 USE_PYTHON=	autoplist concurrent distutils
 
 NO_ARCH=	yes
Index: dns/py-dnspython/Makefile
===================================================================
--- dns/py-dnspython/Makefile
+++ dns/py-dnspython/Makefile
@@ -13,7 +13,7 @@
 LICENSE=	ISCL
 LICENSE_FILE=	${WRKSRC}/LICENSE
 
-USES=		python zip
+USES=		python:2.7+ zip
 USE_PYTHON=	autoplist concurrent cython distutils
 
 NO_ARCH=	yes
Index: lang/cython/Makefile
===================================================================
--- lang/cython/Makefile
+++ lang/cython/Makefile
@@ -14,7 +14,7 @@
 LICENSE=	APACHE20
 LICENSE_FILE=	${WRKSRC}/LICENSE.txt
 
-USES=		compiler:c11 python
+USES=		compiler:c11 python:2.7+
 USE_PYTHON=	allflavors autoplist concurrent distutils
 
 post-install:
Index: misc/py-tqdm/Makefile
===================================================================
--- misc/py-tqdm/Makefile
+++ misc/py-tqdm/Makefile
@@ -15,7 +15,7 @@
 
 BUILD_DEPENDS=	${PYTHON_PKGNAMEPREFIX}setuptools_scm>=3.4:devel/py-setuptools_scm@${PY_FLAVOR}
 
-USES=		python
+USES=		python:2.7+
 USE_PYTHON=	autoplist concurrent distutils
 
 NO_ARCH=	yes
Index: textproc/py-markupsafe/Makefile
===================================================================
--- textproc/py-markupsafe/Makefile
+++ textproc/py-markupsafe/Makefile
@@ -15,7 +15,7 @@
 LICENSE=	BSD3CLAUSE
 LICENSE_FILE=	${WRKSRC}/LICENSE.rst
 
-USES=		python
+USES=		python:2.7+
 USE_PYTHON=	autoplist concurrent distutils
 
 post-install:
Index: textproc/py-pygments-25/Makefile
===================================================================
--- textproc/py-pygments-25/Makefile
+++ textproc/py-pygments-25/Makefile
@@ -16,7 +16,7 @@
 LICENSE=	BSD2CLAUSE
 LICENSE_FILE=	${WRKSRC}/LICENSE
 
-USES=		python
+USES=		python:2.7+
 USE_PYTHON=	distutils concurrent autoplist
 
 CONFLICTS_INSTALL=	py??-pygments
Index: textproc/py-toml/Makefile
===================================================================
--- textproc/py-toml/Makefile
+++ textproc/py-toml/Makefile
@@ -13,7 +13,7 @@
 LICENSE=	MIT
 LICENSE_FILE=	${WRKSRC}/LICENSE
 
-USES=		python
+USES=		python:2.7+
 USE_PYTHON=	autoplist concurrent distutils
 
 NO_ARCH=	yes
Index: www/py-html5lib/Makefile
===================================================================
--- www/py-html5lib/Makefile
+++ www/py-html5lib/Makefile
@@ -17,7 +17,7 @@
 		${PYTHON_PKGNAMEPREFIX}webencodings>0:converters/py-webencodings@${PY_FLAVOR}
 
 NO_ARCH=	yes
-USES=		python
+USES=		python:2.7+
 USE_PYTHON=	autoplist distutils
 
 .include <bsd.port.mk>
Index: x11-toolkits/py-tkinter/Makefile
===================================================================
--- x11-toolkits/py-tkinter/Makefile
+++ x11-toolkits/py-tkinter/Makefile
@@ -16,7 +16,7 @@
 
 PORTSCOUT=	ignore:1
 
-USES=		compiler:c11 python tar:xz tk
+USES=		compiler:c11 python:2.7+ tar:xz tk
 USE_PYTHON=	distutils autoplist allflavors
 
 DIST_SUBDIR=	python