Thank you very much. There's a lot that's different between my install and yours (see below). Although Netbox pins the versions of its direct dependencies, the current policy is not to pin the ancestor dependencies. Unfortunately that results in hard-to-debug problems.
If you could open a bug ticket, giving the *exact* steps to reproduce (including the venv setup), that would be very helpful.
Brian.
--- pip_list_candlerb.txt 2020-02-15 10:09:11.233606928 +0000
+++ pip_list_mucholoco.txt 2020-02-15 10:10:58.291518315 +0000
@@ -1,26 +1,24 @@
Package Version
------------------------- ----------------------
-asn1crypto 0.24.0
-bcrypt 3.1.4
-blinker 1.3
-certifi 2018.10.15
-cffi 1.11.5
-chainmap 1.0.2
+------------------------ ----------
+attrs 19.3.0
+backcall 0.1.0
+bcrypt 3.1.7
+certifi 2019.11.28
+cffi 1.14.0
chardet 3.0.4
-click 6.7
-cloud-init 19.2
-command-not-found 0.3
-configobj 5.0.6
+ciscoconfparse 1.4.11
+Click 7.0
+colorama 0.4.3
coreapi 2.3.3
coreschema 0.0.4
-cryptography 2.3.1
+cryptography 2.8
+decorator 4.4.1
Django 2.2.10
django-cacheops 4.2
django-cors-headers 3.2.1
django-debug-toolbar 2.1
-django-extensions 2.1.4
django-filter 2.2.0
-django-js-asset 1.1.0
+django-js-asset 1.2.2
django-mptt 0.9.1
django-prometheus 1.1.0
django-rq 2.2.0
@@ -31,95 +29,68 @@
djangorestframework 3.10.3
dnspython 1.16.0
drf-yasg 1.17.0
-flex 6.13.2
-funcy 1.12
-future 0.17.1
-graphviz 0.10.1
-gunicorn 19.9.0
-idna 2.7
+funcy 1.14
+future 0.18.2
+gunicorn 20.0.4
+idna 2.8
+importlib-metadata 1.5.0
inflection 0.3.1
+ipython 7.12.0
+ipython-genutils 0.2.0
itypes 1.1.0
+jedi 0.16.0
Jinja2 2.10.3
-jsonpatch 1.10
-jsonpointer 1.14
-jsonschema 2.6.0
-jtextfsm 0.3.1
-junos-eznc 2.1.6
-language-selector 0.1
-librouteros 1.0.3
-lxml 4.2.5
+jsonschema 3.2.0
+junos-eznc 2.2.1
+lxml 4.5.0
Markdown 2.6.11
-MarkupSafe 1.1.0
-napalm 2.3.3
-napalm-base 0.25.0
-napalm-eos 0.6.1
-napalm-fortios 0.4.0
-napalm-ios 0.7.0
-napalm-iosxr 0.5.4
-napalm-junos 0.12.0
-napalm-nxos 0.6.0
-napalm-panos 0.4.0
-napalm-pluribus 0.5.1
-napalm-ros 0.2.2
-napalm-vyos 0.1.3
-natsort 5.3.3
-ncclient 0.6.0
+MarkupSafe 1.1.1
+napalm 2.5.0
+napalm-asa 0.1.1
+ncclient 0.6.7
netaddr 0.7.19
-netmiko 2.3.0
-oauthlib 1.0.3
-olefile 0.44
-openapi-codec 1.3.2
-packaging 20.0
-pan-python 0.12.0
-paramiko 2.4.2
+netmiko 2.4.2
+nxapi-plumbing 0.5.2
+packaging 20.1
+paramiko 2.7.1
+parso 0.6.1
+passlib 1.7.2
+pexpect 4.8.0
+pickleshare 0.7.5
Pillow 7.0.0
-pip 19.0.2
-prettytable 0.7.2
+pip 20.0.2
+pkg-resources 0.0.0
prometheus-client 0.7.1
+prompt-toolkit 3.0.3
psycopg2-binary 2.8.4
+ptyprocess 0.6.0
py-gfm 0.1.4
-pyasn1 0.4.4
pycparser 2.19
pycryptodome 3.9.4
-pycurl 7.43.0
-pyeapi 0.8.1
-pyfg 0.50
-pygobject 3.20.0
+pyeapi 0.8.3
+Pygments 2.5.2
pyIOSXR 0.53
-PyJWT 1.3.0
PyNaCl 1.3.0
-pynetbox 4.0.8
-pynxos 0.0.3
+pynetbox 4.2.5
pyparsing 2.4.6
-pyPluribus 0.3.1
-pyserial 3.0.1
-python-apt 1.1.0b1+ubuntu0.16.4.8
-python-debian 0.1.27
-python-systemd 231
-pytz 2018.7
-PyYAML 3.13
+pyrsistent 0.15.7
+pyserial 3.4
+pytz 2019.3
+PyYAML 5.3
redis 3.3.11
-requests 2.20.0
-requests-toolbelt 0.8.0
-rfc3987 1.3.8
-rq 1.0
-ruamel.yaml 0.15.76
-scp 0.10.2
-setuptools 40.5.0
-simplejson 3.13.2
-six 1.11.0
-sqlparse 0.2.4
-ssh-import-id 5.5
-strict-rfc3339 0.7
+requests 2.22.0
+rq 1.2.2
+ruamel.yaml 0.16.10
+ruamel.yaml.clib 0.2.0
+scp 0.13.2
+setuptools 45.2.0
+six 1.14.0
+sqlparse 0.3.0
svgwrite 1.3.1
-swagger-spec-validator 2.4.1
-textfsm 0.4.1
-ufw 0.35
-unattended-upgrades 0.1
-uritemplate 3.0.0
-urllib3 1.24.1
-validate-email 1.3
-VyattaConfParser 0.5.1
-wheel 0.29.0
-whitenoise 4.1.1
-xmltodict 0.11.0
+swagger-spec-validator 2.4.3
+textfsm 1.1.0
+traitlets 4.3.3
+uritemplate 3.0.1
+urllib3 1.25.8
+wcwidth 0.1.8
+zipp 2.2.0