Comment # 4 on bug 1163747 from pgnd _

> If you run
> python3 -c 'import concurrent; print(concurrent)'
> what happens? (In some random directory, and then in the directory where you wanted clone your ngnix)

random dir:

    python3 -c 'import concurrent; print(concurrent)'
        <module 'concurrent' from
'/usr/lib64/python3.6/concurrent/__init__.py'>

target clone dir:

    python3 -c 'import concurrent; print(concurrent)'
        <module 'concurrent' from
'/usr/lib64/python3.6/concurrent/__init__.py'>

>  Could you share the output of `hg config --debug`, `which hg` and `head $(which hg)`?

(1)

rpm -qa mercurial
    mercurial-4.5.2-lp151.5.1.x86_64

hg config --debug
    starting pager for command 'config'
          1 read config from:
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc
          2 read config from: /usr/etc/mercurial/hgrc
          3 read config from: /etc/mercurial/hgrc
          4 read config from: /etc/mercurial/hgrc.d/cacerts.rc
          5 set config by: $EDITOR
          6 set config by: $VISUAL
          7 set config by: $PAGER
          8 read config from: /root/.hgrc
          9 read config from: /root/.config/hg/hgrc
         10
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:4:
merge-tools.kdiff3.args=--auto --L1 base --L2     10  local --L3 other $base
$local $other -o $output
         11
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:5:
merge-tools.kdiff3.regkey=Software\KDiff3
         12
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:6:
merge-tools.kdiff3.regkeyalt=Software\Wow6432     12 Node\KDiff3
         13
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:7:
merge-tools.kdiff3.regappend=\kdiff3.exe
         14
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:8:
merge-tools.kdiff3.fixeol=True
         15
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:9:
merge-tools.kdiff3.gui=True
         16
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:10:
merge-tools.kdiff3.diffargs=--L1 $plabel1 --     16 L2 $clabel $parent $child
         17
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:12:
merge-tools.gvimdiff.args=--nofork -d -g -O      17 $local $other $base
         18
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:13:
merge-tools.gvimdiff.regkey=Software\Vim\GVi     18 m
         19
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:14:
merge-tools.gvimdiff.regkeyalt=Software\Wow6     19 432Node\Vim\GVim
         20
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:15:
merge-tools.gvimdiff.regname=path
         21
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:16:
merge-tools.gvimdiff.priority=-9
         22
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:17:
merge-tools.gvimdiff.diffargs=--nofork -d -g     22  -O $parent $child
         23
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:19:
merge-tools.vimdiff.args=$local $other $base     23  -c 'redraw | echomsg "hg
merge conflict, type \":cq\" to abort vimdiff"'
         24
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:20:
merge-tools.vimdiff.check=changed
         25
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:21:
merge-tools.vimdiff.priority=-10
         26
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:23:
merge-tools.merge.check=conflicts
         27
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:24:
merge-tools.merge.priority=-100
         28
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:26:
merge-tools.gpyfm.gui=True
         29
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:28:
merge-tools.meld.gui=True
         30
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:29:
merge-tools.meld.args=--label='local' $local     30  --label='merged' $base
--label='other' $other -o $output
         31
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:30:
merge-tools.meld.check=changed
         32
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:31:
merge-tools.meld.diffargs=-a --label=$plabel     32 1 $parent --label=$clabel
$child
         33
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:33:
merge-tools.tkdiff.args=$local $other -a $ba     33 se -o $output
         34
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:34:
merge-tools.tkdiff.gui=True
         35
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:35:
merge-tools.tkdiff.priority=-8
         36
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:36:
merge-tools.tkdiff.diffargs=-L $plabel1 $par     36 ent -L $clabel $child
         37
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:38:
merge-tools.xxdiff.args=--show-merged-pane -     37 -exit-with-merge-status
--title1 local --title2 base --title3 other --merged-filename $output --merge
$local $base $o     37 ther
         38
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:39:
merge-tools.xxdiff.gui=True
         39
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:40:
merge-tools.xxdiff.priority=-8
         40
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:41:
merge-tools.xxdiff.diffargs=--title1 $plabel     40 1 $parent --title2 $clabel
$child
         41
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:43:
merge-tools.diffmerge.regkey=Software\Source     41 Gear\SourceGear DiffMerge\
         42
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:44:
merge-tools.diffmerge.regkeyalt=Software\Wow     42
6432Node\SourceGear\SourceGear DiffMerge\
         43
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:45:
merge-tools.diffmerge.regname=Location
         44
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:46:
merge-tools.diffmerge.priority=-7
         45
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:47:
merge-tools.diffmerge.args=-nosplash -merge      45 -title1=local
-title2=merged -title3=other $local $base $other -result=$output
         46
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:48:
merge-tools.diffmerge.check=changed
         47
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:49:
merge-tools.diffmerge.gui=True
         48
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:50:
merge-tools.diffmerge.diffargs=--nosplash --     48 title1=$plabel1
--title2=$clabel $parent $child
         49
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:52:
merge-tools.p4merge.args=$base $local $other     49  $output
         50
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:53:
merge-tools.p4merge.regkey=Software\Perforce     50 \Environment
         51
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:54:
merge-tools.p4merge.regkeyalt=Software\Wow64     51 32Node\Perforce\Environment
         52
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:55:
merge-tools.p4merge.regname=P4INSTROOT
         53
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:56:
merge-tools.p4merge.regappend=\p4merge.exe
         54
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:57:
merge-tools.p4merge.gui=True
         55
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:58:
merge-tools.p4merge.priority=-8
         56
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:59:
merge-tools.p4merge.diffargs=$parent $child
         57
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:61:
merge-tools.p4mergeosx.executable=/Applicati     57
ons/p4merge.app/Contents/MacOS/p4merge
         58
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:62:
merge-tools.p4mergeosx.args=$base $local $ot     58 her $output
         59
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:63:
merge-tools.p4mergeosx.gui=True
         60
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:64:
merge-tools.p4mergeosx.priority=-8
         61
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:65:
merge-tools.p4mergeosx.diffargs=$parent $chi     61 ld
         62
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:67:
merge-tools.tortoisemerge.args=/base:$base /     62 mine:$local /theirs:$other
/merged:$output
         63
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:68:
merge-tools.tortoisemerge.regkey=Software\To     63 rtoiseSVN
         64
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:69:
merge-tools.tortoisemerge.regkeyalt=Software     64 \Wow6432Node\TortoiseSVN
         65
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:70:
merge-tools.tortoisemerge.check=changed
         66
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:71:
merge-tools.tortoisemerge.gui=True
         67
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:72:
merge-tools.tortoisemerge.priority=-8
         68
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:73:
merge-tools.tortoisemerge.diffargs=/base:$pa     68 rent /mine:$child
/basename:$plabel1 /minename:$clabel
         69
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:75:
merge-tools.ecmerge.args=$base $local $other     69  --mode=merge3
--title0=base --title1=local --title2=other --to=$output
         70
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:76:
merge-tools.ecmerge.regkey=Software\Elli\xc3     70 \xa9 Computing\Merge
         71
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:77:
merge-tools.ecmerge.regkeyalt=Software\Wow64     71 32Node\Elli\xc3\xa9
Computing\Merge
         72
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:78:
merge-tools.ecmerge.gui=True
         73
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:79:
merge-tools.ecmerge.diffargs=$parent $child      73 --mode=diff2
--title1=$plabel1 --title2=$clabel
         74
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:83:
merge-tools.editmerge.args=$output
         75
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:84:
merge-tools.editmerge.check=changed
         76
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:85:
merge-tools.editmerge.premerge=keep
         77
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:87:
merge-tools.filemerge.executable=/Developer/     77
Applications/Utilities/FileMerge.app/Contents/MacOS/FileMerge
         78
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:88:
merge-tools.filemerge.args=-left $other -rig     78 ht $local -ancestor $base
-merge $output
         79
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:89:
merge-tools.filemerge.gui=True
         80
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:91:
merge-tools.filemergexcode.executable=/Appli     80
cations/Xcode.app/Contents/Applications/FileMerge.app/Contents/MacOS/FileMerge
         81
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:92:
merge-tools.filemergexcode.args=-left $other     81  -right $local -ancestor
$base -merge $output
         82
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:93:
merge-tools.filemergexcode.gui=True
         83
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:96:
merge-tools.beyondcompare3.args=$local $othe     83 r $base $output /ro
/lefttitle=local /centertitle=base /righttitle=other /automerge
/reviewconflicts /solo
         84
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:97:
merge-tools.beyondcompare3.regkey=Software\S     84 cooter Software\Beyond
Compare 3
         85
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:98:
merge-tools.beyondcompare3.regname=ExePath
         86
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:99:
merge-tools.beyondcompare3.gui=True
         87
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:100:
merge-tools.beyondcompare3.priority=-2
         88
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:101:
merge-tools.beyondcompare3.diffargs=/lro /l     88 efttitle=$plabel1
/righttitle=$clabel /solo /expandall $parent $child
         89
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:104:
merge-tools.bcompare.args=$local $other $ba     89 se -mergeoutput=$output -ro
-lefttitle=parent1 -centertitle=base -righttitle=parent2 -outputtitle=merged
-automerge -     89 reviewconflicts -solo
         90
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:105:
merge-tools.bcompare.gui=True
         91
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:106:
merge-tools.bcompare.priority=-1
         92
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:107:
merge-tools.bcompare.diffargs=-lro -lefttit     92 le=$plabel1
-righttitle=$clabel -solo -expandall $parent $child
         93
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:110:
merge-tools.bcomposx.executable=/Applicatio     93 ns/Beyond
Compare.app/Contents/MacOS/bcomp
         94
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:111:
merge-tools.bcomposx.args=$local $other $ba     94 se -mergeoutput=$output -ro
-lefttitle=parent1 -centertitle=base -righttitle=parent2 -outputtitle=merged
-automerge -     94 reviewconflicts -solo
         95
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:112:
merge-tools.bcomposx.gui=True
         96
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:113:
merge-tools.bcomposx.priority=-1
         97
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:114:
merge-tools.bcomposx.diffargs=-lro -lefttit     97 le=$plabel1
-righttitle=$clabel -solo -expandall $parent $child
         98
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:116:
merge-tools.winmerge.args=/e /x /wl /ub /dl     98  other /dr local $other
$local $output
         99
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:117:
merge-tools.winmerge.regkey=Software\Thinga     99 mahoochie\WinMerge
        100
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:118:
merge-tools.winmerge.regkeyalt=Software\Wow    100
6432Node\Thingamahoochie\WinMerge\
        101
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:119:
merge-tools.winmerge.regname=Executable
        102
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:120:
merge-tools.winmerge.check=changed
        103
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:121:
merge-tools.winmerge.gui=True
        104
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:122:
merge-tools.winmerge.priority=-10
        105
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:123:
merge-tools.winmerge.diffargs=/r /e /x /ub     105 /wl /dl $plabel1 /dr $clabel
$parent $child
        106
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:125:
merge-tools.araxis.regkey=SOFTWARE\Classes\    106
TypeLib\{46799e0a-7bd1-4330-911c-9660bb964ea2}\7.0\HELPDIR
        107
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:126:
merge-tools.araxis.regappend=\ConsoleCompar    107 e.exe
        108
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:127:
merge-tools.araxis.priority=-2
        109
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:128:
merge-tools.araxis.args=/3 /a2 /wait /merge    109  /title1:"Other"
/title2:"Base" /title3:"Local :"$local $other $base $local $output
        110
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:129:
merge-tools.araxis.checkconflict=True
        111
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:130:
merge-tools.araxis.binary=True
        112
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:131:
merge-tools.araxis.gui=True
        113
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:132:
merge-tools.araxis.diffargs=/2 /wait /title    113 1:$plabel1 /title2:$clabel
$parent $child
        114
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:134:
merge-tools.diffuse.priority=-3
        115
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:135:
merge-tools.diffuse.args=$local $base $othe    115 r
        116
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:136:
merge-tools.diffuse.gui=True
        117
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:137:
merge-tools.diffuse.diffargs=$parent $child
        118
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:139:
merge-tools.UltraCompare.regkey=Software\Mi    118
crosoft\Windows\CurrentVersion\App Paths\UC.exe
        119
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:140:
merge-tools.UltraCompare.regkeyalt=Software    119
\Wow6432Node\Microsoft\Windows\CurrentVersion\App Paths\UC.exe
        120
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:141:
merge-tools.UltraCompare.args=$base $local     120 $other -title1 base -title3
other
        121
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:142:
merge-tools.UltraCompare.priority=-2
        122
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:143:
merge-tools.UltraCompare.gui=True
        123
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:144:
merge-tools.UltraCompare.binary=True
        124
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:145:
merge-tools.UltraCompare.check=conflicts,ch    124 anged
        125
/usr/lib64/python2.7/site-packages/mercurial/default.d/mergetools.rc:146:
merge-tools.UltraCompare.diffargs=$child $p    125 arent -title1 $clabel
-title2 $plabel1
        126 $PAGER: pager.pager=/usr/bin/less
        127 $VISUAL: ui.editor=/usr/bin/joe -tab 4
        128 --verbose: ui.verbose=False
        129 --debug: ui.debug=True
        130 --quiet: ui.quiet=False
        131 pager: ui.formatted=True
        132 pager: ui.interactive=False
        133 /etc/mercurial/hgrc.d/cacerts.rc:2:
web.cacerts=/etc/ssl/ca-bundle.pem

which hg
    /usr/bin/hg

head $(which hg)
    #!/usr/bin/python
    #
    # mercurial - scalable distributed SCM
    #
    # Copyright 2005-2007 Matt Mackall <mpm@selenic.com>
    #
    # This software may be used and distributed according to the terms of the
    # GNU General Public License version 2 or any later version.
    from __future__ import absolute_import

hg clone http://hg.nginx.org/njs
    destination directory: njs
    requesting all changes
    adding changesets
    adding manifests
    adding file changes
    added 1326 changesets with 5191 changes to 387 files
    new changesets 157dc59dae36:974e6c195410
    updating to branch default
    211 files updated, 0 files merged, 0 files removed, 0 files unresolved

(2)

zypper up mercurial
rpm -qa mercurial
    mercurial-5.3-lp151.256.1.x86_64

hg config --debug
    Traceback (most recent call last):
      File "/usr/bin/hg", line 43, in <module>
        dispatch.run()
      File
"/usr/lib64/python3.6/site-packages/hgdemandimport/demandimportpy2.py", line
157, in __getattr__
        self._load()
      File
"/usr/lib64/python3.6/site-packages/hgdemandimport/demandimportpy2.py", line
97, in _load
        _origimport, head, globals, locals, None, level
      File
"/usr/lib64/python3.6/site-packages/hgdemandimport/demandimportpy2.py", line
44, in _hgextimport
        return importfunc(name, globals, *args, **kwargs)
      File "/usr/lib64/python3.6/site-packages/mercurial/dispatch.py", line 21,
in <module>
        from .i18n import _
      File
"/usr/lib64/python3.6/site-packages/hgdemandimport/demandimportpy2.py", line
257, in _demandimport
        _origimport, name, globals, locals, level=level
      File
"/usr/lib64/python3.6/site-packages/hgdemandimport/demandimportpy2.py", line
44, in _hgextimport
        return importfunc(name, globals, *args, **kwargs)
      File "/usr/lib64/python3.6/site-packages/mercurial/i18n.py", line 15, in
<module>
        from .pycompat import getattr
      File
"/usr/lib64/python3.6/site-packages/hgdemandimport/demandimportpy2.py", line
257, in _demandimport
        _origimport, name, globals, locals, level=level
      File
"/usr/lib64/python3.6/site-packages/hgdemandimport/demandimportpy2.py", line
44, in _hgextimport
        return importfunc(name, globals, *args, **kwargs)
      File "/usr/lib64/python3.6/site-packages/mercurial/pycompat.py", line 38,
in <module>
        from .thirdparty.concurrent import futures
      File
"/usr/lib64/python3.6/site-packages/hgdemandimport/demandimportpy2.py", line
257, in _demandimport
        _origimport, name, globals, locals, level=level
      File
"/usr/lib64/python3.6/site-packages/hgdemandimport/demandimportpy2.py", line
44, in _hgextimport
        return importfunc(name, globals, *args, **kwargs)
    ImportError: No module named concurrent

which hg
    /usr/bin/hg

head $(which hg)
    #!/usr/bin/python3
    #
    # mercurial - scalable distributed SCM
    #
    # Copyright 2005-2007 Matt Mackall <mpm@selenic.com>
    #
    # This software may be used and distributed according to the terms of the
    # GNU General Public License version 2 or any later version.
    from __future__ import absolute_import

hg clone http://hg.nginx.org/njs
    Traceback (most recent call last):
      File "/usr/bin/hg", line 43, in <module>
        dispatch.run()
      File
"/usr/lib64/python3.6/site-packages/hgdemandimport/demandimportpy2.py", line
157, in __getattr__
        self._load()
      File
"/usr/lib64/python3.6/site-packages/hgdemandimport/demandimportpy2.py", line
97, in _load
        _origimport, head, globals, locals, None, level
      File
"/usr/lib64/python3.6/site-packages/hgdemandimport/demandimportpy2.py", line
44, in _hgextimport
        return importfunc(name, globals, *args, **kwargs)
      File "/usr/lib64/python3.6/site-packages/mercurial/dispatch.py", line 21,
in <module>
        from .i18n import _
      File
"/usr/lib64/python3.6/site-packages/hgdemandimport/demandimportpy2.py", line
257, in _demandimport
        _origimport, name, globals, locals, level=level
      File
"/usr/lib64/python3.6/site-packages/hgdemandimport/demandimportpy2.py", line
44, in _hgextimport
        return importfunc(name, globals, *args, **kwargs)
      File "/usr/lib64/python3.6/site-packages/mercurial/i18n.py", line 15, in
<module>
        from .pycompat import getattr
      File
"/usr/lib64/python3.6/site-packages/hgdemandimport/demandimportpy2.py", line
257, in _demandimport
        _origimport, name, globals, locals, level=level
      File
"/usr/lib64/python3.6/site-packages/hgdemandimport/demandimportpy2.py", line
44, in _hgextimport
        return importfunc(name, globals, *args, **kwargs)
      File "/usr/lib64/python3.6/site-packages/mercurial/pycompat.py", line 38,
in <module>
        from .thirdparty.concurrent import futures
      File
"/usr/lib64/python3.6/site-packages/hgdemandimport/demandimportpy2.py", line
257, in _demandimport
        _origimport, name, globals, locals, level=level
      File
"/usr/lib64/python3.6/site-packages/hgdemandimport/demandimportpy2.py", line
44, in _hgextimport
        return importfunc(name, globals, *args, **kwargs)
    ImportError: No module named concurrent