Coroutine to mimic a OS's scheduler - python-3.x

Question

I am following the :A Curious Course on Coroutines and Concurrency to learn coroutine, encounter problem to get the following codes running:
The code mimic an operating system to schedule tasks
from queue import Quue
class Task:
taskid = 0
def __init__(self, target):
Task.taskid += 1 #count the task
self.tid = Task.taskid
self.tartet = target
self.sendval = None
def run(self):
return self.target.send(self.sendval)
class Scheduler:
def __init__(self):
self.ready = Queue() # a queue of tasks that are ready to run.
self.taskmap = {} #dictionary that keeps track of all active tasks (each task has a unique integer task ID)
def new(self, target): #introduce a new task to the scheduler
newtask = Task(target)
self.taskmap[newtask.tid] = newtask
def schedule(self, task):
self.ready.put(task)
def mainloop(self):
while self.taskmap: #I think the problem is here
task = self.ready.get() #I think it should be while self.ready
result = task.run()
self.schedule(task)
Test it with
def foo():
while True:
print("I'm foo")
yield
def bar():
while True:
print("I'm bar")
yield
It pending instead of return value
In [85]: schedule.new(foo())
In [86]: schedule.new(bar())
In [87]: schedule.mainloop()
^C---------------------------------------------------------------------------
KeyboardInterrupt Traceback (most recent call last)
I review the codes and find problem with
def mainloop(self):
while self.taskmap: #I think the problem is here
task = self.ready.get() #I think it should be while self.ready
result = task.run()
self.schedule(task)
while self.taskmap, but there is no methods to remove elements, so it is an infinite loop
I changed it to
def mainloop(self):
while self.taskmap: #I think the problem is here
task = self.ready.get() #I think it should be while self.ready
result = task.run()
self.schedule(task)
However, it still not work.
What's the problem with my code.