Error: "Can't set attribute"

[Norica]

Hello,

I added a setter, but I still get an error. What do I do wrong?
The class is pretty big so I posted just these pieces of code.

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@property     def deadline(self):         """         Deadline in milliseconds.         """         return self._task_info.deadline           #Added     @deadline.setter     def deadline(self, value):         self._task_info.deadline = value

I want to set the attribute like this:
task.deadline = 22222

And get the error.

[ThomasL]

1) The decorator @property must be correctly aligned with the method.

1 2	@property def deadline(self):

2) what error? Shall we pick a random error we can think of?

[Norica]

I get the error: " Can't set attribute"

[Norica]

1) The decorator @property must be correctly aligned with the method.

1 2	@property def deadline(self):

2) what error? Shall we pick a random error we can think of?

1) Of course.
2) I get the following error: "Can't set attribute"

[ThomasL]

When do you get the error?
What do you do?
Show the complete error message.

[Norica]

When do you get the error?
What do you do?
Show the complete error message.

I get the error when I try to run the program.
I have another .py file called EDV_VD.py where I wrote " task.deadline=2222 " in the 'init' function and I get this error:

Traceback (most recent call last):
File "script.py", line 53, in <module>
main(sys.argv)
File "script.py", line 47, in main
model.run_model()
File "C:\Users\norica\AppData\Local\Programs\Python\Python37\lib\site-packages\simso\core\Model.py", line 133, in run_model
self.scheduler.init()
File "./..//simso//schedulers\EDF_VD.py", line 57, in init
task.deadline = 2222
AttributeError: can't set attribute

[ThomasL]

and task is an instance of that class where the method deadline is defined?

---

what construct is self._task_info?
why is there a self._task_info dot deadline?

[nilamo]

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@property def deadline(self):     """     Deadline in milliseconds.     """     return self._task_info.deadline

Are you modifying a library or something? Can you share your whole class, and how you're trying to use it?

[Norica]

and task is an instance of that class where the method deadline is defined?

---

what construct is self._task_info?
why is there a self._task_info dot deadline?

1. Yes.
2 & 3. Here is the file where I tried to add the setter. It's at line 184.

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# coding=utf-8   from collections import deque from SimPy.Simulation import Process, Monitor, hold, passivate from simso.core.Job import Job from simso.core.Timer import Timer from simso.core.CSDP import CSDP   import os import os.path     class TaskInfo(object):     """     TaskInfo is mainly a container class grouping the data that characterize     a Task. A list of TaskInfo objects are passed to the Model so that     :class:`Task` instances can be created.     """       def __init__(self, name, identifier, task_type, abort_on_miss, period,                  activation_date, n_instr, mix, stack_file, wcet, acet,                  et_stddev, deadline, base_cpi, followed_by,                  list_activation_dates, preemption_cost, data, my_parameter):         """         :type name: str         :type identifier: int         :type task_type: str         :type abort_on_miss: bool         :type period: float         :type activation_date: float         :type n_instr: int         :type mix: float         :type stack_file: str         :type wcet: float         :type acet: float         :type et_stddev: float         :type deadline: float         :type base_cpi: float         :type followed_by: int         :type list_activation_dates: list         :type preemption_cost: int         :type data: dict         :type my_parameter: float         """         self.name = name         self.identifier = identifier         self.task_type = task_type         self.period = period         self.activation_date = activation_date         self.n_instr = n_instr         self.mix = mix         self.wcet = wcet         self.acet = acet         self.et_stddev = et_stddev         self.base_cpi = base_cpi         self._stack = None         self._csdp = None         self._stack_file = ''         self.set_stack_file(*stack_file)         self.deadline = deadline         self.followed_by = followed_by         self.abort_on_miss = abort_on_miss         self.list_activation_dates = list_activation_dates         self.data = data         self.preemption_cost = preemption_cost         self.my_parameter = my_parameter       @property     def csdp(self):         """         Accumulated Stack Distance Profile. Used by the cache models instead of         the Stack Distance Profile for optimization matters.         """         return self._csdp       @property     def stack_file(self):         """         Stack distance profile input file.         """         return self._stack_file       def set_stack_file(self, stack_file, cur_dir):         """         Set the stack distance profile.         """         if stack_file:             try:                 self._stack = TaskInfo._parse_stack(stack_file)                 self._csdp = CSDP(self._stack)                 self._stack_file = os.path.relpath(stack_file, cur_dir)             except Exception as e:                 print("set_stack_file failed:", e)       @staticmethod     def _parse_stack(stack_file):         stack = {}         if stack_file and os.path.isfile(stack_file):             for line in open(stack_file):                 dist, value = line.split()                 stack[int(dist)] = float(value)         else:             stack = None         return stack     class GenericTask(Process):     """     Abstract class for Tasks. :class:`ATask` and :class:`PTask` inherits from     this class.       These classes simulate the behavior of the simulated task. It controls the     release of the jobs and is able to abort the jobs that exceed their     deadline.       The majority of the task_info attributes are available through this class     too. A set of metrics such as the number of preemptions and migrations are     available for analysis.     """     fields = []       def __init__(self, sim, task_info):         """         Args:           - `sim`: :class:`Model <simso.core.Model>` instance.         - `task_info`: A :class:`TaskInfo` representing the Task.           :type sim: Model         :type task_info: TaskInfo         """         Process.__init__(self, name=task_info.name, sim=sim)         self.name = task_info.name         self._task_info = task_info         self._monitor = Monitor(name="Monitor" + self.name + "_states",                                 sim=sim)         self._activations_fifo = deque([])         self._sim = sim         self.cpu = None         self._etm = sim.etm         self._job_count = 0         self._last_cpu = None         self._cpi_alone = {}         self._jobs = []         self.job = None                           def __lt__(self, other):         return self.identifier < other.identifier       def is_active(self):         return self.job is not None and self.job.is_active()       def set_cpi_alone(self, proc, cpi):         self._cpi_alone[proc] = cpi       def get_cpi_alone(self, proc=None):         if proc is None:             proc = self.cpu         return self._cpi_alone[proc]       @property     def base_cpi(self):         return self._task_info.base_cpi       @property     def data(self):         """         Extra data to characterize the task. Only used by the scheduler.         """         return self._task_info.data       @property     def deadline(self):         """         Deadline in milliseconds.         """         return self._task_info.deadline           #Added     @deadline.setter     def deadline(self, value):         self._task_info.deadline = value                     @property     def n_instr(self):         return self._task_info.n_instr       @property     def mix(self):         return self._task_info.mix       @property     def csdp(self):         return self._task_info.csdp       @property     def preemption_cost(self):         return self._task_info.preemption_cost       @property     def footprint(self):         return int(self._task_info.n_instr * self._task_info.mix *                    (1 - self._task_info.csdp.get(-1)))       @property     def wcet(self):         """Worst-Case Execution Time in milliseconds."""         return self._task_info.wcet     #Added     @wcet.setter     def set_wcet(self, value):         'setting'         self._task_info.wcet = value         @property     def acet(self):         return self._task_info.acet           @property     def my_parameter(self):         return self._task_info.my_parameter       @property     def et_stddev(self):         return self._task_info.et_stddev       @property     def period(self):         """         Period of the task.         """         return self._task_info.period       #Added     @period.setter     def period(self,value):         'setting'         self._task_info.period = value         @property     def identifier(self):         """         Identifier of the task.         """         return self._task_info.identifier       @property     def monitor(self):         """         The monitor for this Task. Similar to a log mechanism (see Monitor in         SimPy doc).         """         return self._monitor       @property     def followed_by(self):         """         Task that is activated by the end of a job from this task.         """         if self._task_info.followed_by is not None:             followed = [x for x in self._sim.task_list                         if (x.identifier == self._task_info.followed_by)]             if followed:                 return followed[0]         return None       @property     def jobs(self):         """         List of the jobs.         """         return self._jobs       def end_job(self, job):         self._last_cpu = self.cpu         if self.followed_by:             self.followed_by.create_job(job)           if len(self._activations_fifo) > 0:             self._activations_fifo.popleft()         if len(self._activations_fifo) > 0:             self.job = self._activations_fifo[0]             self.sim.activate(self.job, self.job.activate_job())       def _job_killer(self, job):         if job.end_date is None and job.computation_time < job.wcet:             if self._task_info.abort_on_miss:                 self.cancel(job)                 job.abort()       def create_job(self, pred=None):         """         Create a new job from this task. This should probably not be used         directly by a scheduler.         """         self._job_count += 1         job = Job(self, "{}_{}".format(self.name, self._job_count), pred,                   monitor=self._monitor, etm=self._etm, sim=self.sim)           if len(self._activations_fifo) == 0:             self.job = job             self.sim.activate(job, job.activate_job())         self._activations_fifo.append(job)         self._jobs.append(job)           timer_deadline = Timer(self.sim, GenericTask._job_killer,                                (self, job), self.deadline)         timer_deadline.start()       def _init(self):         if self.cpu is None:             self.cpu = self._sim.processors[0]     class ATask(GenericTask):     """     Non-periodic Task process. Inherits from :class:`GenericTask`. The job is     created by another task.     """     fields = ['deadline', 'wcet', 'my_parameter']       def execute(self):         self._init()         yield passivate, self      class PTask(GenericTask):     """     Periodic Task process. Inherits from :class:`GenericTask`. The jobs are     created periodically.     """     fields = ['activation_date', 'period', 'deadline', 'wcet', 'my_parameter']       def execute(self):         self._init()         # wait the activation date.         yield hold, self, int(self._task_info.activation_date *                               self._sim.cycles_per_ms)           while True:             #print self.sim.now(), "activate", self.name             self.create_job()             yield hold, self, int(self.period * self._sim.cycles_per_ms)            class SporadicTask(GenericTask):     """     Sporadic Task process. Inherits from :class:`GenericTask`. The jobs are     created using a list of activation dates.     """     fields = ['list_activation_dates', 'deadline', 'wcet', 'my_parameter']       def execute(self):           self._init()         for ndate in self.list_activation_dates:             yield hold, self, int(ndate * self._sim.cycles_per_ms) \                 - self._sim.now()             self.create_job()       @property     def list_activation_dates(self):         return self._task_info.list_activation_dates       task_types = {     "Periodic": PTask,     "APeriodic": ATask,     "Sporadic": SporadicTask }   task_types_names = ["Periodic", "APeriodic", "Sporadic"]     def Task(sim, task_info):     """     Task factory. Return and instantiate the correct class according to the     task_info.     """       return task_types[task_info.task_type](sim, task_info)

---

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@property def deadline(self):     """     Deadline in milliseconds.     """     return self._task_info.deadline

Are you modifying a library or something? Can you share your whole class, and how you're trying to use it?

Yes. I tried to modify a library. At line 184 I added the setter.
And in another file, on an instance of the class PTask, which I called "task", I tried to set its deadline.

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# coding=utf-8   from collections import deque from SimPy.Simulation import Process, Monitor, hold, passivate from simso.core.Job import Job from simso.core.Timer import Timer from simso.core.CSDP import CSDP   import os import os.path     class TaskInfo(object):     """     TaskInfo is mainly a container class grouping the data that characterize     a Task. A list of TaskInfo objects are passed to the Model so that     :class:`Task` instances can be created.     """       def __init__(self, name, identifier, task_type, abort_on_miss, period,                  activation_date, n_instr, mix, stack_file, wcet, acet,                  et_stddev, deadline, base_cpi, followed_by,                  list_activation_dates, preemption_cost, data, my_parameter):         """         :type name: str         :type identifier: int         :type task_type: str         :type abort_on_miss: bool         :type period: float         :type activation_date: float         :type n_instr: int         :type mix: float         :type stack_file: str         :type wcet: float         :type acet: float         :type et_stddev: float         :type deadline: float         :type base_cpi: float         :type followed_by: int         :type list_activation_dates: list         :type preemption_cost: int         :type data: dict         :type my_parameter: float         """         self.name = name         self.identifier = identifier         self.task_type = task_type         self.period = period         self.activation_date = activation_date         self.n_instr = n_instr         self.mix = mix         self.wcet = wcet         self.acet = acet         self.et_stddev = et_stddev         self.base_cpi = base_cpi         self._stack = None         self._csdp = None         self._stack_file = ''         self.set_stack_file(*stack_file)         self.deadline = deadline         self.followed_by = followed_by         self.abort_on_miss = abort_on_miss         self.list_activation_dates = list_activation_dates         self.data = data         self.preemption_cost = preemption_cost         self.my_parameter = my_parameter       @property     def csdp(self):         """         Accumulated Stack Distance Profile. Used by the cache models instead of         the Stack Distance Profile for optimization matters.         """         return self._csdp       @property     def stack_file(self):         """         Stack distance profile input file.         """         return self._stack_file       def set_stack_file(self, stack_file, cur_dir):         """         Set the stack distance profile.         """         if stack_file:             try:                 self._stack = TaskInfo._parse_stack(stack_file)                 self._csdp = CSDP(self._stack)                 self._stack_file = os.path.relpath(stack_file, cur_dir)             except Exception as e:                 print("set_stack_file failed:", e)       @staticmethod     def _parse_stack(stack_file):         stack = {}         if stack_file and os.path.isfile(stack_file):             for line in open(stack_file):                 dist, value = line.split()                 stack[int(dist)] = float(value)         else:             stack = None         return stack     class GenericTask(Process):     """     Abstract class for Tasks. :class:`ATask` and :class:`PTask` inherits from     this class.       These classes simulate the behavior of the simulated task. It controls the     release of the jobs and is able to abort the jobs that exceed their     deadline.       The majority of the task_info attributes are available through this class     too. A set of metrics such as the number of preemptions and migrations are     available for analysis.     """     fields = []       def __init__(self, sim, task_info):         """         Args:           - `sim`: :class:`Model <simso.core.Model>` instance.         - `task_info`: A :class:`TaskInfo` representing the Task.           :type sim: Model         :type task_info: TaskInfo         """         Process.__init__(self, name=task_info.name, sim=sim)         self.name = task_info.name         self._task_info = task_info         self._monitor = Monitor(name="Monitor" + self.name + "_states",                                 sim=sim)         self._activations_fifo = deque([])         self._sim = sim         self.cpu = None         self._etm = sim.etm         self._job_count = 0         self._last_cpu = None         self._cpi_alone = {}         self._jobs = []         self.job = None                           def __lt__(self, other):         return self.identifier < other.identifier       def is_active(self):         return self.job is not None and self.job.is_active()       def set_cpi_alone(self, proc, cpi):         self._cpi_alone[proc] = cpi       def get_cpi_alone(self, proc=None):         if proc is None:             proc = self.cpu         return self._cpi_alone[proc]       @property     def base_cpi(self):         return self._task_info.base_cpi       @property     def data(self):         """         Extra data to characterize the task. Only used by the scheduler.         """         return self._task_info.data       @property     def deadline(self):         """         Deadline in milliseconds.         """         return self._task_info.deadline           #Added     @deadline.setter     def deadline(self, value):         self._task_info.deadline = value                     @property     def n_instr(self):         return self._task_info.n_instr       @property     def mix(self):         return self._task_info.mix       @property     def csdp(self):         return self._task_info.csdp       @property     def preemption_cost(self):         return self._task_info.preemption_cost       @property     def footprint(self):         return int(self._task_info.n_instr * self._task_info.mix *                    (1 - self._task_info.csdp.get(-1)))       @property     def wcet(self):         """Worst-Case Execution Time in milliseconds."""         return self._task_info.wcet     #Added     @wcet.setter     def set_wcet(self, value):         'setting'         self._task_info.wcet = value         @property     def acet(self):         return self._task_info.acet           @property     def my_parameter(self):         return self._task_info.my_parameter       @property     def et_stddev(self):         return self._task_info.et_stddev       @property     def period(self):         """         Period of the task.         """         return self._task_info.period       #Added     @period.setter     def period(self,value):         'setting'         self._task_info.period = value         @property     def identifier(self):         """         Identifier of the task.         """         return self._task_info.identifier       @property     def monitor(self):         """         The monitor for this Task. Similar to a log mechanism (see Monitor in         SimPy doc).         """         return self._monitor       @property     def followed_by(self):         """         Task that is activated by the end of a job from this task.         """         if self._task_info.followed_by is not None:             followed = [x for x in self._sim.task_list                         if (x.identifier == self._task_info.followed_by)]             if followed:                 return followed[0]         return None       @property     def jobs(self):         """         List of the jobs.         """         return self._jobs       def end_job(self, job):         self._last_cpu = self.cpu         if self.followed_by:             self.followed_by.create_job(job)           if len(self._activations_fifo) > 0:             self._activations_fifo.popleft()         if len(self._activations_fifo) > 0:             self.job = self._activations_fifo[0]             self.sim.activate(self.job, self.job.activate_job())       def _job_killer(self, job):         if job.end_date is None and job.computation_time < job.wcet:             if self._task_info.abort_on_miss:                 self.cancel(job)                 job.abort()       def create_job(self, pred=None):         """         Create a new job from this task. This should probably not be used         directly by a scheduler.         """         self._job_count += 1         job = Job(self, "{}_{}".format(self.name, self._job_count), pred,                   monitor=self._monitor, etm=self._etm, sim=self.sim)           if len(self._activations_fifo) == 0:             self.job = job             self.sim.activate(job, job.activate_job())         self._activations_fifo.append(job)         self._jobs.append(job)           timer_deadline = Timer(self.sim, GenericTask._job_killer,                                (self, job), self.deadline)         timer_deadline.start()       def _init(self):         if self.cpu is None:             self.cpu = self._sim.processors[0]     class ATask(GenericTask):     """     Non-periodic Task process. Inherits from :class:`GenericTask`. The job is     created by another task.     """     fields = ['deadline', 'wcet', 'my_parameter']       def execute(self):         self._init()         yield passivate, self      class PTask(GenericTask):     """     Periodic Task process. Inherits from :class:`GenericTask`. The jobs are     created periodically.     """     fields = ['activation_date', 'period', 'deadline', 'wcet', 'my_parameter']       def execute(self):         self._init()         # wait the activation date.         yield hold, self, int(self._task_info.activation_date *                               self._sim.cycles_per_ms)           while True:             #print self.sim.now(), "activate", self.name             self.create_job()             yield hold, self, int(self.period * self._sim.cycles_per_ms)            class SporadicTask(GenericTask):     """     Sporadic Task process. Inherits from :class:`GenericTask`. The jobs are     created using a list of activation dates.     """     fields = ['list_activation_dates', 'deadline', 'wcet', 'my_parameter']       def execute(self):           self._init()         for ndate in self.list_activation_dates:             yield hold, self, int(ndate * self._sim.cycles_per_ms) \                 - self._sim.now()             self.create_job()       @property     def list_activation_dates(self):         return self._task_info.list_activation_dates       task_types = {     "Periodic": PTask,     "APeriodic": ATask,     "Sporadic": SporadicTask }   task_types_names = ["Periodic", "APeriodic", "Sporadic"]     def Task(sim, task_info):     """     Task factory. Return and instantiate the correct class according to the     task_info.     """       return task_types[task_info.task_type](sim, task_info)