fix missing import, version bump

[Batcastle]

We need a version bump cause version 2.3.1 is already being used. So this fix includes a version bump

[pep8speaks]

Hello @Batcastle! Thanks for opening this PR. We checked the lines you've touched for PEP 8 issues, and found:

• In the file usr/share/system-installer/oem/pre_install.py:

Line 36:1: E402 module level import not at top of file
Line 65:80: E501 line too long (80 > 79 characters)
Line 68:80: E501 line too long (80 > 79 characters)
Line 71:80: E501 line too long (83 > 79 characters)
Line 90:80: E501 line too long (89 > 79 characters)
Line 91:80: E501 line too long (100 > 79 characters)
Line 117:80: E501 line too long (84 > 79 characters)
Line 190:80: E501 line too long (85 > 79 characters)
Line 206:80: E501 line too long (80 > 79 characters)
Line 238:80: E501 line too long (80 > 79 characters)
Line 247:80: E501 line too long (91 > 79 characters)
Line 321:80: E501 line too long (85 > 79 characters)
Line 328:80: E501 line too long (81 > 79 characters)
Line 334:80: E501 line too long (90 > 79 characters)
Line 344:80: E501 line too long (98 > 79 characters)
Line 367:80: E501 line too long (85 > 79 characters)
Line 393:80: E501 line too long (91 > 79 characters)
Line 396:80: E501 line too long (107 > 79 characters)
Line 402:80: E501 line too long (94 > 79 characters)
Line 404:80: E501 line too long (100 > 79 characters)
Line 407:80: E501 line too long (87 > 79 characters)
Line 409:80: E501 line too long (115 > 79 characters)
Line 411:43: E711 comparison to None should be 'if cond is not None:'
Line 412:80: E501 line too long (82 > 79 characters)
Line 416:80: E501 line too long (89 > 79 characters)
Line 418:80: E501 line too long (89 > 79 characters)
Line 424:80: E501 line too long (85 > 79 characters)
Line 444:80: E501 line too long (103 > 79 characters)
Line 468:5: E303 too many blank lines (2)
Line 565:1: E303 too many blank lines (3)