Failing build on CircleCI

[stigrj]

CircleCI fails with the following message (complete output):

#!/bin/bash -eo pipefail
pipenv install --three

Creating a virtualenv for this project...
Pipfile: /home/merzbow/vampyr/Pipfile
Using /usr/bin/python3 (3.6.5) to create virtualenv...
Already using interpreter /usr/bin/python3
Using base prefix '/usr'
New python executable in /home/merzbow/.local/share/virtualenvs/vampyr-YejbnMRG/bin/python3
Also creating executable in /home/merzbow/.local/share/virtualenvs/vampyr-YejbnMRG/bin/python
Installing setuptools, pip, wheel...done.
Setting project for vampyr-YejbnMRG to /home/merzbow/vampyr

Virtualenv location: /home/merzbow/.local/share/virtualenvs/vampyr-YejbnMRG
Pipfile.lock not found, creating...
Locking [dev-packages] dependencies...
Locking [packages] dependencies...
env/utils.py", line 402, in resolve_deps
    req_dir=req_dir
  File "/usr/local/lib/python3.6/dist-packages/pipenv/utils.py", line 250, in actually_resolve_deps
    req = Requirement.from_line(dep)
  File "/usr/local/lib/python3.6/dist-packages/pipenv/vendor/requirementslib/models/requirements.py", line 704, in from_line
    line, extras = _strip_extras(line)
TypeError: 'module' object is not callable

Exited with code 1

[robertodr]

Seems related to this pypa/pipenv#2924 I think I need to update the Docker image. I am suprised this isn't happening for MRChem. I wonder whether CircleCI caches the Docker images 🤔