I've done a little more investigation and now I'm more confused. When
$ sudo pip3 install -v meson
Collecting meson
1 location(s) to search for versions of meson:
Current age based on date: 333
Freshness lifetime from max-age: 600
Freshness lifetime from request max-age: 600
The response is "fresh", returning cached response
600 > 333
Using version 0.32.0 (newest of versions: 0.29.0, 0.30.0, 0.31.0, 0.32.0)
Current age based on date: 333
Freshness lifetime from max-age: 31557600
The response is "fresh", returning cached response
31557600 > 333
Using cached meson-0.32.0.tar.gz
Running setup.py (path:/tmp/pip-build-zhelr_sc/meson/setup.py) egg_info for package meson
Running command python setup.py egg_info
running egg_info
creating pip-egg-info/meson.egg-info
writing top-level names to pip-egg-info/meson.egg-info/top_level.txt
writing pip-egg-info/meson.egg-info/PKG-INFO
writing dependency_links to pip-egg-info/meson.egg-info/dependency_links.txt
writing manifest file 'pip-egg-info/meson.egg-info/SOURCES.txt'
warning: manifest_maker: standard file '-c' not found
reading manifest file 'pip-egg-info/meson.egg-info/SOURCES.txt'
reading manifest template 'MANIFEST.in'
warning: no files found matching 'readme.txt'
writing manifest file 'pip-egg-info/meson.egg-info/SOURCES.txt'
Installing collected packages: meson
Running setup.py install for meson ... Running command /usr/bin/python -u -c "import setuptools, tokenize;__file__='/tmp/pip-build-zhelr_sc/meson/setup.py';exec(compile(getattr(tokenize, 'open', open)(__file__).read().replace('\r\n', '\n'), __file__, 'exec'))" install --record /tmp/pip-8m8lktyg-record/install-record.txt --single-version-externally-managed --compile
running install
running build
running build_py
creating build
creating build/lib
creating build/lib/mesonbuild
copying mesonbuild/optinterpreter.py -> build/lib/mesonbuild
copying mesonbuild/mparser.py -> build/lib/mesonbuild
copying mesonbuild/mlog.py -> build/lib/mesonbuild
copying mesonbuild/mintro.py -> build/lib/mesonbuild
copying mesonbuild/mesonmain.py -> build/lib/mesonbuild
copying mesonbuild/mesonlib.py -> build/lib/mesonbuild
copying mesonbuild/mconf.py -> build/lib/mesonbuild
copying mesonbuild/interpreter.py -> build/lib/mesonbuild
copying mesonbuild/environment.py -> build/lib/mesonbuild
copying mesonbuild/dependencies.py -> build/lib/mesonbuild
copying mesonbuild/coredata.py -> build/lib/mesonbuild
copying mesonbuild/compilers.py -> build/lib/mesonbuild
copying mesonbuild/build.py -> build/lib/mesonbuild
copying mesonbuild/__init__.py -> build/lib/mesonbuild
creating build/lib/mesonbuild/modules
copying mesonbuild/modules/windows.py -> build/lib/mesonbuild/modules
copying mesonbuild/modules/rpm.py -> build/lib/mesonbuild/modules
copying mesonbuild/modules/qt5.py -> build/lib/mesonbuild/modules
copying mesonbuild/modules/qt4.py -> build/lib/mesonbuild/modules
copying mesonbuild/modules/pkgconfig.py -> build/lib/mesonbuild/modules
copying mesonbuild/modules/modtest.py -> build/lib/mesonbuild/modules
copying mesonbuild/modules/i18n.py -> build/lib/mesonbuild/modules
copying mesonbuild/modules/gnome.py -> build/lib/mesonbuild/modules
copying mesonbuild/modules/__init__.py -> build/lib/mesonbuild/modules
creating build/lib/mesonbuild/scripts
copying mesonbuild/scripts/vcstagger.py -> build/lib/mesonbuild/scripts
copying mesonbuild/scripts/symbolextractor.py -> build/lib/mesonbuild/scripts
copying mesonbuild/scripts/scanbuild.py -> build/lib/mesonbuild/scripts
copying mesonbuild/scripts/regen_checker.py -> build/lib/mesonbuild/scripts
copying mesonbuild/scripts/meson_test.py -> build/lib/mesonbuild/scripts
copying mesonbuild/scripts/meson_install.py -> build/lib/mesonbuild/scripts
copying mesonbuild/scripts/meson_exe.py -> build/lib/mesonbuild/scripts
copying mesonbuild/scripts/meson_benchmark.py -> build/lib/mesonbuild/scripts
copying mesonbuild/scripts/gtkdochelper.py -> build/lib/mesonbuild/scripts
copying mesonbuild/scripts/gettext.py -> build/lib/mesonbuild/scripts
copying mesonbuild/scripts/dirchanger.py -> build/lib/mesonbuild/scripts
copying mesonbuild/scripts/depfixer.py -> build/lib/mesonbuild/scripts
copying mesonbuild/scripts/delwithsuffix.py -> build/lib/mesonbuild/scripts
copying mesonbuild/scripts/commandrunner.py -> build/lib/mesonbuild/scripts
copying mesonbuild/scripts/__init__.py -> build/lib/mesonbuild/scripts
creating build/lib/mesonbuild/backend
copying mesonbuild/backend/xcodebackend.py -> build/lib/mesonbuild/backend
copying mesonbuild/backend/vs2015backend.py -> build/lib/mesonbuild/backend
copying mesonbuild/backend/vs2010backend.py -> build/lib/mesonbuild/backend
copying mesonbuild/backend/ninjabackend.py -> build/lib/mesonbuild/backend
copying mesonbuild/backend/backends.py -> build/lib/mesonbuild/backend
copying mesonbuild/backend/__init__.py -> build/lib/mesonbuild/backend
creating build/lib/mesonbuild/wrap
copying mesonbuild/wrap/wraptool.py -> build/lib/mesonbuild/wrap
copying mesonbuild/wrap/wrap.py -> build/lib/mesonbuild/wrap
copying mesonbuild/wrap/__init__.py -> build/lib/mesonbuild/wrap
running build_scripts
creating build/scripts-3.5
copying and adjusting meson.py -> build/scripts-3.5
copying and adjusting mesonconf.py -> build/scripts-3.5
copying and adjusting mesonintrospect.py -> build/scripts-3.5
copying and adjusting wraptool.py -> build/scripts-3.5
changing mode of build/scripts-3.5/meson.py from 644 to 755
changing mode of build/scripts-3.5/mesonconf.py from 644 to 755
changing mode of build/scripts-3.5/mesonintrospect.py from 644 to 755
changing mode of build/scripts-3.5/wraptool.py from 644 to 755
running install_lib
creating /usr/lib/python3.5/site-packages/mesonbuild
creating /usr/lib/python3.5/site-packages/mesonbuild/wrap
copying build/lib/mesonbuild/wrap/__init__.py -> /usr/lib/python3.5/site-packages/mesonbuild/wrap
copying build/lib/mesonbuild/wrap/wrap.py -> /usr/lib/python3.5/site-packages/mesonbuild/wrap
copying build/lib/mesonbuild/wrap/wraptool.py -> /usr/lib/python3.5/site-packages/mesonbuild/wrap
creating /usr/lib/python3.5/site-packages/mesonbuild/backend
copying build/lib/mesonbuild/backend/__init__.py -> /usr/lib/python3.5/site-packages/mesonbuild/backend
copying build/lib/mesonbuild/backend/backends.py -> /usr/lib/python3.5/site-packages/mesonbuild/backend
copying build/lib/mesonbuild/backend/ninjabackend.py -> /usr/lib/python3.5/site-packages/mesonbuild/backend
copying build/lib/mesonbuild/backend/vs2010backend.py -> /usr/lib/python3.5/site-packages/mesonbuild/backend
copying build/lib/mesonbuild/backend/vs2015backend.py -> /usr/lib/python3.5/site-packages/mesonbuild/backend
copying build/lib/mesonbuild/backend/xcodebackend.py -> /usr/lib/python3.5/site-packages/mesonbuild/backend
creating /usr/lib/python3.5/site-packages/mesonbuild/scripts
copying build/lib/mesonbuild/scripts/__init__.py -> /usr/lib/python3.5/site-packages/mesonbuild/scripts
copying build/lib/mesonbuild/scripts/commandrunner.py -> /usr/lib/python3.5/site-packages/mesonbuild/scripts
copying build/lib/mesonbuild/scripts/delwithsuffix.py -> /usr/lib/python3.5/site-packages/mesonbuild/scripts
copying build/lib/mesonbuild/scripts/depfixer.py -> /usr/lib/python3.5/site-packages/mesonbuild/scripts
copying build/lib/mesonbuild/scripts/dirchanger.py -> /usr/lib/python3.5/site-packages/mesonbuild/scripts
copying build/lib/mesonbuild/scripts/gettext.py -> /usr/lib/python3.5/site-packages/mesonbuild/scripts
copying build/lib/mesonbuild/scripts/gtkdochelper.py -> /usr/lib/python3.5/site-packages/mesonbuild/scripts
copying build/lib/mesonbuild/scripts/meson_benchmark.py -> /usr/lib/python3.5/site-packages/mesonbuild/scripts
copying build/lib/mesonbuild/scripts/meson_exe.py -> /usr/lib/python3.5/site-packages/mesonbuild/scripts
copying build/lib/mesonbuild/scripts/meson_install.py -> /usr/lib/python3.5/site-packages/mesonbuild/scripts
copying build/lib/mesonbuild/scripts/meson_test.py -> /usr/lib/python3.5/site-packages/mesonbuild/scripts
copying build/lib/mesonbuild/scripts/regen_checker.py -> /usr/lib/python3.5/site-packages/mesonbuild/scripts
copying build/lib/mesonbuild/scripts/scanbuild.py -> /usr/lib/python3.5/site-packages/mesonbuild/scripts
copying build/lib/mesonbuild/scripts/symbolextractor.py -> /usr/lib/python3.5/site-packages/mesonbuild/scripts
copying build/lib/mesonbuild/scripts/vcstagger.py -> /usr/lib/python3.5/site-packages/mesonbuild/scripts
creating /usr/lib/python3.5/site-packages/mesonbuild/modules
copying build/lib/mesonbuild/modules/__init__.py -> /usr/lib/python3.5/site-packages/mesonbuild/modules
copying build/lib/mesonbuild/modules/gnome.py -> /usr/lib/python3.5/site-packages/mesonbuild/modules
copying build/lib/mesonbuild/modules/i18n.py -> /usr/lib/python3.5/site-packages/mesonbuild/modules
copying build/lib/mesonbuild/modules/modtest.py -> /usr/lib/python3.5/site-packages/mesonbuild/modules
copying build/lib/mesonbuild/modules/pkgconfig.py -> /usr/lib/python3.5/site-packages/mesonbuild/modules
copying build/lib/mesonbuild/modules/qt4.py -> /usr/lib/python3.5/site-packages/mesonbuild/modules
copying build/lib/mesonbuild/modules/qt5.py -> /usr/lib/python3.5/site-packages/mesonbuild/modules
copying build/lib/mesonbuild/modules/rpm.py -> /usr/lib/python3.5/site-packages/mesonbuild/modules
copying build/lib/mesonbuild/modules/windows.py -> /usr/lib/python3.5/site-packages/mesonbuild/modules
copying build/lib/mesonbuild/__init__.py -> /usr/lib/python3.5/site-packages/mesonbuild
copying build/lib/mesonbuild/build.py -> /usr/lib/python3.5/site-packages/mesonbuild
copying build/lib/mesonbuild/compilers.py -> /usr/lib/python3.5/site-packages/mesonbuild
copying build/lib/mesonbuild/coredata.py -> /usr/lib/python3.5/site-packages/mesonbuild
copying build/lib/mesonbuild/dependencies.py -> /usr/lib/python3.5/site-packages/mesonbuild
copying build/lib/mesonbuild/environment.py -> /usr/lib/python3.5/site-packages/mesonbuild
copying build/lib/mesonbuild/interpreter.py -> /usr/lib/python3.5/site-packages/mesonbuild
copying build/lib/mesonbuild/mconf.py -> /usr/lib/python3.5/site-packages/mesonbuild
copying build/lib/mesonbuild/mesonlib.py -> /usr/lib/python3.5/site-packages/mesonbuild
copying build/lib/mesonbuild/mesonmain.py -> /usr/lib/python3.5/site-packages/mesonbuild
copying build/lib/mesonbuild/mintro.py -> /usr/lib/python3.5/site-packages/mesonbuild
copying build/lib/mesonbuild/mlog.py -> /usr/lib/python3.5/site-packages/mesonbuild
copying build/lib/mesonbuild/mparser.py -> /usr/lib/python3.5/site-packages/mesonbuild
copying build/lib/mesonbuild/optinterpreter.py -> /usr/lib/python3.5/site-packages/mesonbuild
byte-compiling /usr/lib/python3.5/site-packages/mesonbuild/wrap/__init__.py to __init__.cpython-35.pyc
byte-compiling /usr/lib/python3.5/site-packages/mesonbuild/wrap/wrap.py to wrap.cpython-35.pyc
byte-compiling /usr/lib/python3.5/site-packages/mesonbuild/wrap/wraptool.py to wraptool.cpython-35.pyc
byte-compiling /usr/lib/python3.5/site-packages/mesonbuild/backend/__init__.py to __init__.cpython-35.pyc
byte-compiling /usr/lib/python3.5/site-packages/mesonbuild/backend/backends.py to backends.cpython-35.pyc
byte-compiling /usr/lib/python3.5/site-packages/mesonbuild/backend/ninjabackend.py to ninjabackend.cpython-35.pyc
byte-compiling /usr/lib/python3.5/site-packages/mesonbuild/backend/vs2010backend.py to vs2010backend.cpython-35.pyc
byte-compiling /usr/lib/python3.5/site-packages/mesonbuild/backend/vs2015backend.py to vs2015backend.cpython-35.pyc
byte-compiling /usr/lib/python3.5/site-packages/mesonbuild/backend/xcodebackend.py to xcodebackend.cpython-35.pyc
byte-compiling /usr/lib/python3.5/site-packages/mesonbuild/scripts/__init__.py to __init__.cpython-35.pyc
byte-compiling /usr/lib/python3.5/site-packages/mesonbuild/scripts/commandrunner.py to commandrunner.cpython-35.pyc
byte-compiling /usr/lib/python3.5/site-packages/mesonbuild/scripts/delwithsuffix.py to delwithsuffix.cpython-35.pyc
byte-compiling /usr/lib/python3.5/site-packages/mesonbuild/scripts/depfixer.py to depfixer.cpython-35.pyc
byte-compiling /usr/lib/python3.5/site-packages/mesonbuild/scripts/dirchanger.py to dirchanger.cpython-35.pyc
byte-compiling /usr/lib/python3.5/site-packages/mesonbuild/scripts/gettext.py to gettext.cpython-35.pyc
byte-compiling /usr/lib/python3.5/site-packages/mesonbuild/scripts/gtkdochelper.py to gtkdochelper.cpython-35.pyc
byte-compiling /usr/lib/python3.5/site-packages/mesonbuild/scripts/meson_benchmark.py to meson_benchmark.cpython-35.pyc
byte-compiling /usr/lib/python3.5/site-packages/mesonbuild/scripts/meson_exe.py to meson_exe.cpython-35.pyc
byte-compiling /usr/lib/python3.5/site-packages/mesonbuild/scripts/meson_install.py to meson_install.cpython-35.pyc
byte-compiling /usr/lib/python3.5/site-packages/mesonbuild/scripts/meson_test.py to meson_test.cpython-35.pyc
byte-compiling /usr/lib/python3.5/site-packages/mesonbuild/scripts/regen_checker.py to regen_checker.cpython-35.pyc
byte-compiling /usr/lib/python3.5/site-packages/mesonbuild/scripts/scanbuild.py to scanbuild.cpython-35.pyc
byte-compiling /usr/lib/python3.5/site-packages/mesonbuild/scripts/symbolextractor.py to symbolextractor.cpython-35.pyc
byte-compiling /usr/lib/python3.5/site-packages/mesonbuild/scripts/vcstagger.py to vcstagger.cpython-35.pyc
byte-compiling /usr/lib/python3.5/site-packages/mesonbuild/modules/__init__.py to __init__.cpython-35.pyc
byte-compiling /usr/lib/python3.5/site-packages/mesonbuild/modules/gnome.py to gnome.cpython-35.pyc
byte-compiling /usr/lib/python3.5/site-packages/mesonbuild/modules/i18n.py to i18n.cpython-35.pyc
byte-compiling /usr/lib/python3.5/site-packages/mesonbuild/modules/modtest.py to modtest.cpython-35.pyc
byte-compiling /usr/lib/python3.5/site-packages/mesonbuild/modules/pkgconfig.py to pkgconfig.cpython-35.pyc
byte-compiling /usr/lib/python3.5/site-packages/mesonbuild/modules/qt4.py to qt4.cpython-35.pyc
byte-compiling /usr/lib/python3.5/site-packages/mesonbuild/modules/qt5.py to qt5.cpython-35.pyc
byte-compiling /usr/lib/python3.5/site-packages/mesonbuild/modules/rpm.py to rpm.cpython-35.pyc
byte-compiling /usr/lib/python3.5/site-packages/mesonbuild/modules/windows.py to windows.cpython-35.pyc
byte-compiling /usr/lib/python3.5/site-packages/mesonbuild/__init__.py to __init__.cpython-35.pyc
byte-compiling /usr/lib/python3.5/site-packages/mesonbuild/build.py to build.cpython-35.pyc
byte-compiling /usr/lib/python3.5/site-packages/mesonbuild/compilers.py to compilers.cpython-35.pyc
byte-compiling /usr/lib/python3.5/site-packages/mesonbuild/coredata.py to coredata.cpython-35.pyc
byte-compiling /usr/lib/python3.5/site-packages/mesonbuild/dependencies.py to dependencies.cpython-35.pyc
byte-compiling /usr/lib/python3.5/site-packages/mesonbuild/environment.py to environment.cpython-35.pyc
byte-compiling /usr/lib/python3.5/site-packages/mesonbuild/interpreter.py to interpreter.cpython-35.pyc
byte-compiling /usr/lib/python3.5/site-packages/mesonbuild/mconf.py to mconf.cpython-35.pyc
byte-compiling /usr/lib/python3.5/site-packages/mesonbuild/mesonlib.py to mesonlib.cpython-35.pyc
byte-compiling /usr/lib/python3.5/site-packages/mesonbuild/mesonmain.py to mesonmain.cpython-35.pyc
byte-compiling /usr/lib/python3.5/site-packages/mesonbuild/mintro.py to mintro.cpython-35.pyc
byte-compiling /usr/lib/python3.5/site-packages/mesonbuild/mlog.py to mlog.cpython-35.pyc
byte-compiling /usr/lib/python3.5/site-packages/mesonbuild/mparser.py to mparser.cpython-35.pyc
byte-compiling /usr/lib/python3.5/site-packages/mesonbuild/optinterpreter.py to optinterpreter.cpython-35.pyc
running install_data
copying man/meson.1 -> /usr/share/man/man1
copying man/mesonconf.1 -> /usr/share/man/man1
copying man/mesonintrospect.1 -> /usr/share/man/man1
copying man/wraptool.1 -> /usr/share/man/man1
running install_egg_info
running egg_info
writing top-level names to meson.egg-info/top_level.txt
writing dependency_links to meson.egg-info/dependency_links.txt
writing meson.egg-info/PKG-INFO
warning: manifest_maker: standard file '-c' not found
reading manifest file 'meson.egg-info/SOURCES.txt'
reading manifest template 'MANIFEST.in'
warning: no files found matching 'readme.txt'
writing manifest file 'meson.egg-info/SOURCES.txt'
Copying meson.egg-info to /usr/lib/python3.5/site-packages/meson-0.32.0-py3.5.egg-info
running install_scripts
copying build/scripts-3.5/wraptool.py -> /usr/bin
copying build/scripts-3.5/mesonintrospect.py -> /usr/bin
copying build/scripts-3.5/mesonconf.py -> /usr/bin
copying build/scripts-3.5/meson.py -> /usr/bin
changing mode of /usr/bin/wraptool.py to 755
changing mode of /usr/bin/mesonintrospect.py to 755
changing mode of /usr/bin/mesonconf.py to 755
changing mode of /usr/bin/meson.py to 755
writing list of installed files to '/tmp/pip-8m8lktyg-record/install-record.txt'
done
Removing source in /tmp/pip-build-zhelr_sc/meson
Successfully installed meson-0.32.0
Cleaning up...