python-bpmn-engine:在Python流程中解析和执行Camunda BPMN模型

# A python module for parsing and executing BPMN models in a single process Supported elements so far: - Start/end events - Task (Manual, User, Service) - dummy execution for now - Gateways (Exclusive, Parallel) - Sequence flow with conditions Example BPMN model:  Example usage: ```python import asyncio from bpmn_model import BpmnModel m = BpmnModel("models/model_01.bpmn") p1 = m.run("1", {"a": 1}) p2 = m.run("2", {"a": 2}) run = [p1, p2] def run_serial(): for i, p in enumerate(run): print(f"Running process {i+1}\n-----------------") asyncio.run(p) print() def run_parallel(): async def parallel(): await asyncio.gather(p1, p2) print(f"Running processes\n-----------------") asyncio.run(parallel()) # run_parallel() run_serial() ``` Example execution trace: ```python Running process 1 ----------------- [1] DOING: UserTask(Task 1) [1] DOING: Task(DOWN) [1] - waiting for all processes in gate. [1] DOING: Task(UP) [1] DOING: ManualTask(Manual Task 2) [1] DOING: ServiceTask(Task 3) [1] - checking variables={'a': 1} with ['a==1']... [1] DONE: Result is True [1] - going down default path... [1] DOING: Task(Task down) [1] DONE Running process 2 ----------------- [2] DOING: UserTask(Task 1) [2] DOING: Task(DOWN) [2] - waiting for all processes in gate. [2] DOING: Task(UP) [2] DOING: ManualTask(Manual Task 2) [2] DOING: ServiceTask(Task 3) [2] - checking variables={'a': 2} with ['a==1']... [2] DONE: Result is False [2] - going down default path... [2] DOING: Task(Task down) [2] DONE ```