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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def find_workflow_path(self):
 """ Tries to find the path of the workflow diagram file in `WORKFLOW_PACKAGES_PATHS`. Returns: Path of the workflow spec file (BPMN diagram) """

        for pth in settings.WORKFLOW_PACKAGES_PATHS:
            path = "%s/%s.bpmn" % (pth, self.current.workflow_name)
            if os.path.exists(path):
                return path
        err_msg = "BPMN file cannot found: %s" % self.current.workflow_name
        log.error(err_msg)
        raise RuntimeError(err_msg)