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Django-fsm first came out in 2010 and had a big update in 2.0 release at 2014, making it incompatible with earlier versions. Now, ten years later at 2024, it's been updated to version 3.0 and renamed viewflow.fsm.

This new version has a different API that doesn't work with the old one but is better suited for today's needs.

Migration guide:

https://github.com/viewflow/viewflow/wiki/django%E2%80%90fsm-to-viewflow.fsm-Migration-Guide

Finite state machine workflows is the declarative way to describe consecutiveoperation through set of states and transitions between them.

:mod:`viewflow.fsm` can help you manage rules and restrictions around movingfrom one state to another. The package could be used to get low leveldb-independent fsm implementation, or to wrap existing database model, andimplement simple persistent workflow process with quickly bootstrapped UI.

All things are buit around:class:`viewflow.fsm.State`. It is the special classslot, that can take a value only from a specific`python enum`_ or`djangoenumeration type`_ and that value can't be changed with simple assignement.

from enum import Enumfrom viewflow.fsm import Stateclass Stage(Enum):   NEW = 1   DONE = 2   HIDDEN = 3class MyFlow(object):   state = State(Stage, default=Stage.NEW)   @state.transition(source=Stage.NEW, target=Stage.DONE)   def complete():       pass   @state.transition(source=State.ANY, target=Stage.HIDDEN)   def hide():       passflow = MyFlow()flow.state == Stage.NEW  # Trueflow.state = Stage.DONE  # Raises AttributeErrorflow.complete()flow.state == Stage.DONE  # Trueflow.complete()  # Now raises TransitionNotAllowed

Full documentation available athttps://docs.viewflow.io/fsm/index.html