14 files changed, 11 insertions, 77 deletions
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 9a842fb981..f7336d3970 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -61,8 +61,7 @@ set(GR_BOOST_MIN_VERSION "1.53")
 set(GR_SWIG_MIN_VERSION "3.0.8")
 set(GR_CMAKE_MIN_VERSION "3.5.1")
 set(GR_MAKO_MIN_VERSION "0.4.2")
-set(GR_PYTHON_MIN_VERSION "2.7.6")
-set(GR_PYTHON3_MIN_VERSION "3.6.5")
+set(GR_PYTHON_MIN_VERSION "3.6.5")
 set(GCC_MIN_VERSION "4.8.4")
 set(CLANG_MIN_VERSION "3.4.0")
 set(APPLECLANG_MIN_VERSION "500")
diff --git a/cmake/Modules/GrPython.cmake b/cmake/Modules/GrPython.cmake
index b7f72e666e..92af7f5a65 100644
--- a/cmake/Modules/GrPython.cmake
+++ b/cmake/Modules/GrPython.cmake
@@ -33,18 +33,13 @@ if (PYTHON_EXECUTABLE)
     find_package(PythonInterp ${GR_PYTHON_MIN_VERSION} REQUIRED)
 else (PYTHON_EXECUTABLE)
     message(STATUS "PYTHON_EXECUTABLE not set - using default python3")
-    message(STATUS "Use -DPYTHON_EXECUTABLE=/path/to/python2 to build for python2.")
-    find_package(PythonInterp ${GR_PYTHON3_MIN_VERSION} REQUIRED)
+    find_package(PythonInterp ${GR_PYTHON_MIN_VERSION} REQUIRED)
 endif (PYTHON_EXECUTABLE)
 
-if (${PYTHON_VERSION_MAJOR} VERSION_EQUAL 3)
-    set(PYTHON3 TRUE)
-endif ()
-
 find_package(PythonLibs ${PYTHON_VERSION_MAJOR}.${PYTHON_VERSION_MINOR} EXACT)
 
 if (CMAKE_CROSSCOMPILING)
-    set(QA_PYTHON_EXECUTABLE "/usr/bin/python")
+    set(QA_PYTHON_EXECUTABLE "/usr/bin/python3")
 else (CMAKE_CROSSCOMPILING)
     set(QA_PYTHON_EXECUTABLE ${PYTHON_EXECUTABLE})
 endif(CMAKE_CROSSCOMPILING)
diff --git a/cmake/Modules/GrSwig.cmake b/cmake/Modules/GrSwig.cmake
index 39585ac4be..6dae9246c1 100644
--- a/cmake/Modules/GrSwig.cmake
+++ b/cmake/Modules/GrSwig.cmake
@@ -118,12 +118,8 @@ macro(GR_SWIG_MAKE name)
     list(INSERT GR_SWIG_INCLUDE_DIRS 0 "$<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}>")
     list(INSERT GR_SWIG_INCLUDE_DIRS 0 "$<BUILD_INTERFACE:${CMAKE_CURRENT_BINARY_DIR}>")
 
-    if (PYTHON3)
-        set(py3 "-py3")
-    endif (PYTHON3)
-
     #setup the swig flags with flags and include directories
-    set(CMAKE_SWIG_FLAGS -fvirtual -modern -keyword -w511 -w314 -relativeimport ${py3} -module ${name} ${GR_SWIG_FLAGS})
+    set(CMAKE_SWIG_FLAGS -fvirtual -modern -keyword -w511 -w314 -relativeimport -py3 -module ${name} ${GR_SWIG_FLAGS})
 
     #set the C++ property on the swig .i file so it builds
     set_source_files_properties(${ifiles} PROPERTIES CPLUSPLUS ON)
diff --git a/gnuradio-runtime/swig/CMakeLists.txt b/gnuradio-runtime/swig/CMakeLists.txt
index bade4beeaa..e39693e4c3 100644
--- a/gnuradio-runtime/swig/CMakeLists.txt
+++ b/gnuradio-runtime/swig/CMakeLists.txt
@@ -101,7 +101,6 @@ install(
     msg_queue.i
     pmt_swig.i
     prefs.i
-    py3compat.i
     realtime.i
     sync_block.i
     sync_decimator.i
diff --git a/gnuradio-runtime/swig/basic_block.i b/gnuradio-runtime/swig/basic_block.i
index 363e121bc6..cf75479bb8 100644
--- a/gnuradio-runtime/swig/basic_block.i
+++ b/gnuradio-runtime/swig/basic_block.i
@@ -31,10 +31,6 @@ namespace std {
   %template(x_vector_basic_block_sptr) vector<gr::basic_block_sptr>;
 };
 
-%begin %{
-#define SWIG_PYTHON_2_UNICODE
-%}
-
 namespace gr {
 
   class gr::basic_block
@@ -64,8 +60,6 @@ namespace gr {
 }
 
 #ifdef SWIGPYTHON
-%import py3compat.i
-
 %pythoncode %{
 basic_block_sptr.__repr__ = lambda self: "<basic_block %s (%d)>" % (self.name(), self.unique_id ())
 %}
diff --git a/gnuradio-runtime/swig/gnuradio.i b/gnuradio-runtime/swig/gnuradio.i
index 211f0a92d2..555372eeac 100644
--- a/gnuradio-runtime/swig/gnuradio.i
+++ b/gnuradio-runtime/swig/gnuradio.i
@@ -78,10 +78,5 @@
 // Python 2/3 compatibility
 
 %begin %{
-#define SWIG_PYTHON_2_UNICODE
 #define SWIG_PYTHON_CAST_MODE
 %}
-
-#ifdef SWIGPYTHON
-%import py3compat.i
-#endif
diff --git a/gnuradio-runtime/swig/pmt_swig.i b/gnuradio-runtime/swig/pmt_swig.i
index c6ac444fba..cd529d657e 100644
--- a/gnuradio-runtime/swig/pmt_swig.i
+++ b/gnuradio-runtime/swig/pmt_swig.i
@@ -25,10 +25,6 @@
 %include "std_string.i"
 %include "stdint.i"
 
-%begin %{
-#define SWIG_PYTHON_2_UNICODE
-%}
-
 %{
 #include <boost/shared_ptr.hpp>
 #include <boost/any.hpp>
@@ -79,8 +75,6 @@ namespace pmt {
 %template(pmt_vector_cfloat) std::vector< std::complex<float> >;
 %template(pmt_vector_cdouble) std::vector< std::complex<double> >;
 
-%import py3compat.i
-
 ////////////////////////////////////////////////////////////////////////
 // Language independent exception handler
 ////////////////////////////////////////////////////////////////////////
diff --git a/gnuradio-runtime/swig/py3compat.i b/gnuradio-runtime/swig/py3compat.i
deleted file mode 100644
index 6e726c294f..0000000000
--- a/gnuradio-runtime/swig/py3compat.i
+++ /dev/null
@@ -1,7 +0,0 @@
-%begin %{
-#define SWIG_PYTHON_2_UNICODE
-%}
-
-%pythonbegin %{
-from __future__ import absolute_import
-%}
diff --git a/gr-uhd/apps/uhd_fft b/gr-uhd/apps/uhd_fft
index c9607670cf..2d64e85813 100755
--- a/gr-uhd/apps/uhd_fft
+++ b/gr-uhd/apps/uhd_fft
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 #
 # Copyright 2015-2016,2018 Free Software Foundation, Inc.
 #
diff --git a/gr-utils/python/modtool/cli/base.py b/gr-utils/python/modtool/cli/base.py
index 5fa2b8b7b4..d0259372ff 100644
--- a/gr-utils/python/modtool/cli/base.py
+++ b/gr-utils/python/modtool/cli/base.py
@@ -73,8 +73,6 @@ class CommandCLI(click.Group):
         command is the priority over the same external plug-in command.
         """
         try:
-            if sys.version_info[0] == 2:
-                cmd_name = cmd_name.encode('ascii', 'replace')
             mod = import_module('gnuradio.modtool.cli.' + cmd_name)
         except ImportError:
             return self.commands.get(cmd_name)
diff --git a/gr-utils/python/modtool/core/base.py b/gr-utils/python/modtool/core/base.py
index 55b6f48076..d9f6a3b6e2 100644
--- a/gr-utils/python/modtool/core/base.py
+++ b/gr-utils/python/modtool/core/base.py
@@ -30,22 +30,7 @@ import glob
 import logging
 import itertools
 
-try:
-    from types import SimpleNamespace
-except:
-    # Py2.7 doesn't have SimpleNamespace, soooo use what Py3 docs say is roughly equivalent
-    class SimpleNamespace:
-        def __init__(self, **kwargs):
-            self.__dict__.update(kwargs)
-
-        def __repr__(self):
-            keys = sorted(self.__dict__)
-            items = ("{}={!r}".format(k, self.__dict__[k]) for k in keys)
-            return "{}({})".format(type(self).__name__, ", ".join(items))
-
-        def __eq__(self, other):
-            return self.__dict__ == other.__dict__
-
+from types import SimpleNamespace
 from gnuradio import gr
 from ..tools import get_modname, SCMRepoFactory
 
diff --git a/gr-utils/python/modtool/tests/test_modtool.py b/gr-utils/python/modtool/tests/test_modtool.py
index 957a5e7d54..3cfd735f90 100644
--- a/gr-utils/python/modtool/tests/test_modtool.py
+++ b/gr-utils/python/modtool/tests/test_modtool.py
@@ -64,11 +64,7 @@ class TestModToolCore(unittest.TestCase):
     def setUp(self):
         """ create a new module and block before every test """
         try:
-            try:
-                warnings.simplefilter("ignore", ResourceWarning)
-            except (NameError):
-                # Python2 , Python3 < 3.2 don't know ResourceWarning
-                pass
+            warnings.simplefilter("ignore", ResourceWarning)
             args = {'module_name':'howto',
                     'directory': self.test_dir,
                     'srcdir': self.srcdir}
diff --git a/grc/CMakeLists.txt b/grc/CMakeLists.txt
index ba69764f8a..9a807e1cc0 100644
--- a/grc/CMakeLists.txt
+++ b/grc/CMakeLists.txt
@@ -25,10 +25,9 @@ include(GrPython)
 message(STATUS "")
 
 GR_PYTHON_CHECK_MODULE_RAW(
-    "python2 >= 2.7.6 or python3 >= 3.6.5"
+    "python3 >= ${GR_PYTHON_MIN_VERSION}"
     "import sys; \
-     requirement = (3, 6, 5) if sys.version_info.major >= 3 else (2, 7, 6); \
-     assert sys.version_info[:3] >= requirement"
+    assert '.'.join([str(x) for x in sys.version_info[:3]]) >= '${GR_PYTHON_MIN_VERSION}'"
     PYTHON_MIN_VER_FOUND
 )
 
@@ -39,8 +38,8 @@ GR_PYTHON_CHECK_MODULE_RAW(
 )
 
 GR_PYTHON_CHECK_MODULE_RAW(
-    "mako >= 0.9.1"
-    "import mako; assert mako.__version__ >= '0.9.1'"
+    "mako >= ${GR_MAKO_MIN_VERSION}"
+    "import mako; assert mako.__version__ >= '${GR_MAKO_MIN_VERSION}'"
     MAKO_FOUND
 )
 
diff --git a/grc/core/generator/flow_graph.py.mako b/grc/core/generator/flow_graph.py.mako
index 8da3011749..3fb540d8d1 100644
--- a/grc/core/generator/flow_graph.py.mako
+++ b/grc/core/generator/flow_graph.py.mako
@@ -1,15 +1,6 @@
 % if not generate_options.startswith('hb'):
-<%
-from sys import version_info
-from gnuradio import eng_notation
-python_version = version_info.major
-%>\
-% if python_version == 2:
-#!/usr/bin/env python2
-% elif python_version == 3:
 #!/usr/bin/env python3
 % endif
-% endif
 # -*- coding: utf-8 -*-
 <%def name="indent(code)">${ '\n        '.join(str(code).splitlines()) }</%def>
 #