python3 script header and rhel8

[Vladimir Sementsov-Ogievskiy]

Hi all!

Hmm Qemu dropped support for python2, and anyway python2 is not supported now 
at all.

Still, we have a lot of "#!/usr/bin/env python" headings in our scripts, which 
is
unsupported by rhel8 by default. So, for example, because of such line in
tests/qemu-iotests/nbd-fault-injector.py, iotest 277 fails.

Of course, it's simple to set python in rhel8 to be python3... But should we fix
all the headings to be "#!/usr/bin/env python3"? Or what is the correct heading
for scripts in a new python3 world?


# git grep -l '^#!/usr/bin/env python$'
scripts/analyse-9p-simpletrace.py
scripts/analyse-locks-simpletrace.py
scripts/decodetree.py
scripts/device-crash-test
scripts/kvm/kvm_flightrecorder
scripts/qapi-gen.py
scripts/render_block_graph.py
scripts/replay-dump.py
scripts/simpletrace.py
scripts/tracetool.py
scripts/tracetool/__init__.py
scripts/tracetool/backend/__init__.py
scripts/tracetool/backend/dtrace.py
scripts/tracetool/backend/ftrace.py
scripts/tracetool/backend/log.py
scripts/tracetool/backend/simple.py
scripts/tracetool/backend/syslog.py
scripts/tracetool/backend/ust.py
scripts/tracetool/format/__init__.py
scripts/tracetool/format/c.py
scripts/tracetool/format/d.py
scripts/tracetool/format/h.py
scripts/tracetool/format/log_stap.py
scripts/tracetool/format/simpletrace_stap.py
scripts/tracetool/format/stap.py
scripts/tracetool/format/tcg_h.py
scripts/tracetool/format/tcg_helper_c.py
scripts/tracetool/format/tcg_helper_h.py
scripts/tracetool/format/tcg_helper_wrapper_h.py
scripts/tracetool/format/ust_events_c.py
scripts/tracetool/format/ust_events_h.py
scripts/tracetool/transform.py
scripts/tracetool/vcpu.py
tests/acceptance/virtio_seg_max_adjust.py
tests/acceptance/x86_cpu_model_versions.py
tests/docker/travis.py
tests/qapi-schema/test-qapi.py
tests/qemu-iotests/030
tests/qemu-iotests/040
tests/qemu-iotests/041
tests/qemu-iotests/044
tests/qemu-iotests/045
tests/qemu-iotests/055
tests/qemu-iotests/056
tests/qemu-iotests/057
tests/qemu-iotests/065
tests/qemu-iotests/093
tests/qemu-iotests/096
tests/qemu-iotests/118
tests/qemu-iotests/124
tests/qemu-iotests/129
tests/qemu-iotests/132
tests/qemu-iotests/136
tests/qemu-iotests/139
tests/qemu-iotests/147
tests/qemu-iotests/148
tests/qemu-iotests/149
tests/qemu-iotests/151
tests/qemu-iotests/152
tests/qemu-iotests/155
tests/qemu-iotests/163
tests/qemu-iotests/165
tests/qemu-iotests/169
tests/qemu-iotests/194
tests/qemu-iotests/196
tests/qemu-iotests/199
tests/qemu-iotests/202
tests/qemu-iotests/203
tests/qemu-iotests/205
tests/qemu-iotests/206
tests/qemu-iotests/207
tests/qemu-iotests/208
tests/qemu-iotests/209
tests/qemu-iotests/210
tests/qemu-iotests/211
tests/qemu-iotests/212
tests/qemu-iotests/213
tests/qemu-iotests/216
tests/qemu-iotests/218
tests/qemu-iotests/219
tests/qemu-iotests/222
tests/qemu-iotests/224
tests/qemu-iotests/228
tests/qemu-iotests/234
tests/qemu-iotests/235
tests/qemu-iotests/236
tests/qemu-iotests/237
tests/qemu-iotests/238
tests/qemu-iotests/242
tests/qemu-iotests/245
tests/qemu-iotests/246
tests/qemu-iotests/248
tests/qemu-iotests/254
tests/qemu-iotests/255
tests/qemu-iotests/256
tests/qemu-iotests/257
tests/qemu-iotests/258
tests/qemu-iotests/260
tests/qemu-iotests/262
tests/qemu-iotests/264
tests/qemu-iotests/266
tests/qemu-iotests/277
tests/qemu-iotests/280
tests/qemu-iotests/nbd-fault-injector.py
tests/qemu-iotests/qcow2.py
tests/qemu-iotests/qed.py
tests/vm/basevm.py
tests/vm/centos
tests/vm/fedora
tests/vm/freebsd
tests/vm/netbsd
tests/vm/openbsd
tests/vm/ubuntu.i386



-- 
Best regards,
Vladimir