ERROR: Unable to load entry point swift_plugin = bandersnatch_storage_plugins.swift:SwiftStorage: No module named ‘keystoneauth1’
This solution is missing at the time of installation due to python version, solution:
pip3 install keystoneauth1
Collecting keystoneauth1
Downloading https://files.pythonhosted.org/packages/7c/2e/dcfd2412941244e8a00a568654ce1687a1cab7be05d634ada0b5a078d0a3/keystoneauth1-4.4.0-py3-none-any.whl (314kB)
100% |████████████████████████████████| 317kB 240kB/s
Collecting pbr!=2.1.0,>=2.0.0 (from keystoneauth1)
Downloading https://files.pythonhosted.org/packages/73/c3/d45171501210b0305f4c93fafe50950f0c2228e87034ceb51744bd03ff08/pbr-5.8.0-py2.py3-none-any.whl (112kB)
100% |████████████████████████████████| 122kB 184kB/s
Requirement already satisfied: requests>=2.14.2 in /usr/lib/python3/dist-packages (from keystoneauth1)
Collecting stevedore>=1.20.0 (from keystoneauth1)
Downloading https://files.pythonhosted.org/packages/7a/bc/fcce9e50da73ea23af6d236e05e15db8a02da1099a5e0a479451bcea3833/stevedore-3.5.0-py3-none-any.whl (49kB)
100% |████████████████████████████████| 51kB 166kB/s
Requirement already satisfied: six>=1.10.0 in /usr/lib/python3/dist-packages (from keystoneauth1)
Collecting iso8601>=0.1.11 (from keystoneauth1)
Downloading https://files.pythonhosted.org/packages/df/e5/589bc81d410139ec4e4f37d9af5a50987566abf6d087b3c4fbed708109a9/iso8601-1.0.2-py3-none-any.whl
Collecting os-service-types>=1.2.0 (from keystoneauth1)
Downloading https://files.pythonhosted.org/packages/10/2d/318b2b631f68e0fc221ba8f45d163bf810cdb795cf242fe85ad3e5d45639/os_service_types-1.7.0-py2.py3-none-any.whl
Collecting importlib-metadata>=1.7.0; python_version < “3.8” (from stevedore>=1.20.0->keystoneauth1)
Downloading https://files.pythonhosted.org/packages/c4/1f/e2238896149df09953efcc53bdcc7d23597d6c53e428c30e572eda5ec6eb/importlib_metadata-4.8.2-py3-none-any.whl
Collecting zipp>=0.5 (from importlib-metadata>=1.7.0; python_version < “3.8”->stevedore>=1.20.0->keystoneauth1)
Using cached https://files.pythonhosted.org/packages/bd/df/d4a4974a3e3957fd1c1fa3082366d7fff6e428ddb55f074bf64876f8e8ad/zipp-3.6.0-py3-none-any.whl
Requirement already satisfied: typing-extensions>=3.6.4; python_version < “3.8” in /usr/local/lib/python3.7/dist-packages (from importlib-metadata>=1.7.0; python_version < “3.8”->stevedore>=1.20.0->keystoneauth1)
Installing collected packages: pbr, zipp, importlib-metadata, stevedore, iso8601, os-service-types, keystoneauth1
Successfully installed importlib-metadata-4.8.2 iso8601-1.0.2 keystoneauth1-4.4.0 os-service-types-1.7.0 pbr-5.8.0 stevedore-3.5.0 zipp-3.6.0

ERROR: Unable to load entry point swift_plugin = bandersnatch_storage_plugins.swift:SwiftStorage: No module named ‘swiftclient’
This one was installed with python-swiftclient missing.
Solution:
pip3 install python-swiftclient
Collecting python-swiftclient
Downloading https://files.pythonhosted.org/packages/f6/5f/6784a830e618a89272f8efee784930e614be285a6d3e82986916076fe69e/python_swiftclient-3.13.0-py2.py3-none-any.whl (86kB)
100% |████████████████████████████████| 92kB 281kB/s
Requirement already satisfied: six>=1.9.0 in /usr/lib/python3/dist-packages (from python-swiftclient)
Requirement already satisfied: requests>=1.1.0 in /usr/lib/python3/dist-packages (from python-swiftclient)
Installing collected packages: python-swiftclient
Successfully installed python-swiftclient-3.13.0