dh-python dependency removal changing behaviour of installing virtualenv

root@6de0badbae8b:/# apt-get install --no-install-recommends virtualenv
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following additional packages will be installed:
  ca-certificates libexpat1 libmpdec2 libpython3-stdlib libpython3.6-minimal libpython3.6-stdlib libssl1.1 mime-support openssl python-pip-whl python3 python3-minimal
  python3-pkg-resources python3-virtualenv python3.6 python3.6-minimal
Suggested packages:
  python3-doc python3-tk python3-venv python3-setuptools python3.6-venv python3.6-doc binutils binfmt-support
Recommended packages:
  bzip2 file xz-utils
The following NEW packages will be installed:
  ca-certificates libexpat1 libmpdec2 libpython3-stdlib libpython3.6-minimal libpython3.6-stdlib libssl1.1 mime-support openssl python-pip-whl python3 python3-minimal
  python3-pkg-resources python3-virtualenv python3.6 python3.6-minimal virtualenv
0 upgraded, 17 newly installed, 0 to remove and 43 not upgraded.
Need to get 7375 kB of archives.
After this operation, 29.9 MB of additional disk space will be used.
Do you want to continue? [Y/n] y
Get:1 http://archive.ubuntu.com/ubuntu bionic/main amd64 libssl1.1 amd64 1.1.0g-2ubuntu3 [1128 kB]
Get:2 http://archive.ubuntu.com/ubuntu bionic/main amd64 libpython3.6-minimal amd64 3.6.5-3 [529 kB]
Get:3 http://archive.ubuntu.com/ubuntu bionic/main amd64 libexpat1 amd64 2.2.5-3 [80.2 kB]
Get:4 http://archive.ubuntu.com/ubuntu bionic/main amd64 python3.6-minimal amd64 3.6.5-3 [1425 kB]
Get:5 http://archive.ubuntu.com/ubuntu bionic/main amd64 python3-minimal amd64 3.6.5-2 [23.9 kB]
Get:6 http://archive.ubuntu.com/ubuntu bionic/main amd64 mime-support all 3.60ubuntu1 [30.1 kB]
Get:7 http://archive.ubuntu.com/ubuntu bionic/main amd64 libmpdec2 amd64 2.4.2-1 [82.6 kB]
Get:8 http://archive.ubuntu.com/ubuntu bionic/main amd64 libpython3.6-stdlib amd64 3.6.5-3 [1648 kB]
Get:9 http://archive.ubuntu.com/ubuntu bionic/main amd64 python3.6 amd64 3.6.5-3 [186 kB]
Get:10 http://archive.ubuntu.com/ubuntu bionic/main amd64 libpython3-stdlib amd64 3.6.5-2 [7372 B]
Get:11 http://archive.ubuntu.com/ubuntu bionic/main amd64 python3 amd64 3.6.5-2 [8780 B]
Get:12 http://archive.ubuntu.com/ubuntu bionic/main amd64 openssl amd64 1.1.0g-2ubuntu3 [532 kB]
Get:13 http://archive.ubuntu.com/ubuntu bionic/main amd64 ca-certificates all 20170717 [167 kB]
Get:14 http://archive.ubuntu.com/ubuntu bionic/universe amd64 python-pip-whl all 9.0.1-2 [1379 kB]
Get:15 http://archive.ubuntu.com/ubuntu bionic/main amd64 python3-pkg-resources all 39.0.1-2 [98.8 kB]
Get:16 http://archive.ubuntu.com/ubuntu bionic/universe amd64 python3-virtualenv all 15.1.0+ds-1 [43.2 kB]
Get:17 http://archive.ubuntu.com/ubuntu bionic/universe amd64 virtualenv all 15.1.0+ds-1 [4376 B]
Fetched 7375 kB in 14s (515 kB/s)
debconf: delaying package configuration, since apt-utils is not installed
Selecting previously unselected package libssl1.1:amd64.
(Reading database ... 4416 files and directories currently installed.)
Preparing to unpack .../0-libssl1.1_1.1.0g-2ubuntu3_amd64.deb ...
Unpacking libssl1.1:amd64 (1.1.0g-2ubuntu3) ...
Selecting previously unselected package libpython3.6-minimal:amd64.
Preparing to unpack .../1-libpython3.6-minimal_3.6.5-3_amd64.deb ...
Unpacking libpython3.6-minimal:amd64 (3.6.5-3) ...
Selecting previously unselected package libexpat1:amd64.
Preparing to unpack .../2-libexpat1_2.2.5-3_amd64.deb ...
Unpacking libexpat1:amd64 (2.2.5-3) ...
Selecting previously unselected package python3.6-minimal.
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Selecting previously unselected package mime-support.
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Selecting previously unselected package libmpdec2:amd64.
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Unpacking python3.6 (3.6.5-3) ...
Selecting previously unselected package libpython3-stdlib:amd64.
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Unpacking libpython3-stdlib:amd64 (3.6.5-2) ...
Setting up libssl1.1:amd64 (1.1.0g-2ubuntu3) ...
debconf: unable to initialize frontend: Dialog
debconf: (No usable dialog-like program is installed, so the dialog based frontend cannot be used. at /usr/share/perl5/Debconf/FrontEnd/Dialog.pm line 76.)
debconf: falling back to frontend: Readline
debconf: unable to initialize frontend: Readline
debconf: (Can't locate Term/ReadLine.pm in @INC (you may need to install the Term::ReadLine module) (@INC contains: /etc/perl /usr/local/lib/x86_64-linux-gnu/perl/5.26.1 /usr/local/share/perl/5.26.1 /usr/lib/x86_64-linux-gnu/perl5/5.26 /usr/share/perl5 /usr/lib/x86_64-linux-gnu/perl/5.26 /usr/share/perl/5.26 /usr/local/lib/site_perl /usr/lib/x86_64-linux-gnu/perl-base) at /usr/share/perl5/Debconf/FrontEnd/Readline.pm line 7.)
debconf: falling back to frontend: Teletype
Setting up libpython3.6-minimal:amd64 (3.6.5-3) ...
Setting up libexpat1:amd64 (2.2.5-3) ...
Setting up python3.6-minimal (3.6.5-3) ...
Setting up python3-minimal (3.6.5-2) ...
Selecting previously unselected package python3.
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Selecting previously unselected package python3-virtualenv.
Preparing to unpack .../5-python3-virtualenv_15.1.0+ds-1_all.deb ...
Unpacking python3-virtualenv (15.1.0+ds-1) ...
Selecting previously unselected package virtualenv.
Preparing to unpack .../6-virtualenv_15.1.0+ds-1_all.deb ...
Unpacking virtualenv (15.1.0+ds-1) ...
Setting up mime-support (3.60ubuntu1) ...
Processing triggers for libc-bin (2.26-0ubuntu2.1) ...
Setting up openssl (1.1.0g-2ubuntu3) ...
Setting up ca-certificates (20170717) ...
debconf: unable to initialize frontend: Dialog
debconf: (No usable dialog-like program is installed, so the dialog based frontend cannot be used. at /usr/share/perl5/Debconf/FrontEnd/Dialog.pm line 76.)
debconf: falling back to frontend: Readline
debconf: unable to initialize frontend: Readline
debconf: (Can't locate Term/ReadLine.pm in @INC (you may need to install the Term::ReadLine module) (@INC contains: /etc/perl /usr/local/lib/x86_64-linux-gnu/perl/5.26.1 /usr/local/share/perl/5.26.1 /usr/lib/x86_64-linux-gnu/perl5/5.26 /usr/share/perl5 /usr/lib/x86_64-linux-gnu/perl/5.26 /usr/share/perl/5.26 /usr/local/lib/site_perl /usr/lib/x86_64-linux-gnu/perl-base) at /usr/share/perl5/Debconf/FrontEnd/Readline.pm line 7.)
debconf: falling back to frontend: Teletype
Updating certificates in /etc/ssl/certs...
148 added, 0 removed; done.
Setting up libmpdec2:amd64 (2.4.2-1) ...
Setting up python-pip-whl (9.0.1-2) ...
Setting up libpython3.6-stdlib:amd64 (3.6.5-3) ...
Setting up python3.6 (3.6.5-3) ...
Setting up libpython3-stdlib:amd64 (3.6.5-2) ...
Setting up python3 (3.6.5-2) ...
running python rtupdate hooks for python3.6...
running python post-rtupdate hooks for python3.6...
Setting up python3-pkg-resources (39.0.1-2) ...
Setting up python3-virtualenv (15.1.0+ds-1) ...
Setting up virtualenv (15.1.0+ds-1) ...
Processing triggers for ca-certificates (20170717) ...
Updating certificates in /etc/ssl/certs...
0 added, 0 removed; done.
Running hooks in /etc/ca-certificates/update.d...
done.
Processing triggers for libc-bin (2.26-0ubuntu2.1) ...
root@6de0badbae8b:/# virtualenv
Traceback (most recent call last):
  File "/usr/bin/virtualenv", line 11, in <module>
    load_entry_point('virtualenv==15.1.0', 'console_scripts', 'virtualenv')()
  File "/usr/lib/python3/dist-packages/pkg_resources/__init__.py", line 480, in load_entry_point
    return get_distribution(dist).load_entry_point(group, name)
  File "/usr/lib/python3/dist-packages/pkg_resources/__init__.py", line 2693, in load_entry_point
    return ep.load()
  File "/usr/lib/python3/dist-packages/pkg_resources/__init__.py", line 2324, in load
    return self.resolve()
  File "/usr/lib/python3/dist-packages/pkg_resources/__init__.py", line 2330, in resolve
    module = __import__(self.module_name, fromlist=['__name__'], level=0)
  File "/usr/lib/python3/dist-packages/virtualenv.py", line 25, in <module>
    import distutils.sysconfig
ModuleNotFoundError: No module named 'distutils.sysconfig'
root@6de0badbae8b:/# virtualenv --version
Traceback (most recent call last):
  File "/usr/bin/virtualenv", line 11, in <module>
    load_entry_point('virtualenv==15.1.0', 'console_scripts', 'virtualenv')()
  File "/usr/lib/python3/dist-packages/pkg_resources/__init__.py", line 480, in load_entry_point
    return get_distribution(dist).load_entry_point(group, name)
  File "/usr/lib/python3/dist-packages/pkg_resources/__init__.py", line 2693, in load_entry_point
    return ep.load()
  File "/usr/lib/python3/dist-packages/pkg_resources/__init__.py", line 2324, in load
    return self.resolve()
  File "/usr/lib/python3/dist-packages/pkg_resources/__init__.py", line 2330, in resolve
    module = __import__(self.module_name, fromlist=['__name__'], level=0)
  File "/usr/lib/python3/dist-packages/virtualenv.py", line 25, in <module>
    import distutils.sysconfig
ModuleNotFoundError: No module named 'distutils.sysconfig'

The change of removing dh-python dependency will require that the package is deployed before deploying virtualenv

root@6de0badbae8b:/# apt-cache policy python3
python3:
  Installed: 3.6.5-2
  Candidate: 3.6.5-2
  Version table:
 *** 3.6.5-2 500
        500 http://archive.ubuntu.com/ubuntu bionic/main amd64 Packages
        100 /var/lib/dpkg/status

root@6de0badbae8b:/# apt-cache depends python3
python3
  PreDepends: python3-minimal
  Depends: python3.6
  Depends: libpython3-stdlib
  Suggests: python3-doc
  Suggests: python3-tk
  Suggests: python3-venv
  Replaces: python3-minimal