The get_stack() method of asyncio.task class

Overview:

The get_stack() method returns the stack frame for the wrapped coroutine of the asyncio.Task, at the place of its suspension.
By the time get_stack() is executed, if the Task is already complete or cancelled no stack frame is returned.
When the wrapped coroutine of the Task is exited due to an exception, the get_stack() method returns a list of traceback frames.

Example - get_stack() returning a list of traceback frames:

# Example Python program that prints the stack frames
# of a coroutine terminated by an exception
import asyncio

# A coroutine defintion
async def simplecoro():
   try:
       for i in range(1, 2):
           print("Inside simplecoro: %d"%i)
           raise ValueError("Thrown deliberately")
           await asyncio.sleep(1)
   except ValueError:
       raise

# Yet another coroutine defintion
# that awaits on an object of coroutine simplecoro
async def samplecoro():
   try:
       for i in range(1, 10):
           print("Inside samplecoro: %d"%i)
           await simplecoro()
   except ValueError:
       raise

# A coroutine that creates an asyncio.Task
# and executes it
async def main():
   try:
       t1 = asyncio.create_task(samplecoro())
       await asyncio.sleep(1)

       # Get the stack of the task and print it
       s1 = t1.get_stack()
       print(s1)

       # Suspend main and run t1
       await t1
   except ValueError as e:
       print("Handled exception:%s"%e.args)

# Create and event loop and run the task
el = asyncio.new_event_loop()
asyncio.set_event_loop(el)
el.run_until_complete(main())

Output:

Inside samplecoro: 1

Inside simplecoro: 1

[<frame at 0x1044718c0, file '/Users/vinodh/pprogs/GetStockEx1.py', line 23, code samplecoro>, <frame at 0x104471540, file '/Users/vinodh/pprogs/GetStockEx1.py', line 13, code simplecoro>]

Handled exception:Thrown deliberately

Example - get_stack() returning the stack frame of a suspended coroutine:

# Example Python program that prints the
# stack frame of the wrapped coroutine
# from an asyncio.Task object
import asyncio

# Define a coroutine
async def coro():
   for i in range(1, 10, 2):
       print(i)
       # Suspend coro while waiting
       await asyncio.sleep(1)

# Coroutine that creates and executes Task
async def main(coro):
task = asyncio.create_task(coro)

   # Get stack of the wrapped coroutine
   stack = task.get_stack()
   print(stack)

   # Suspend while task is being run
   await task

# Print the task completion status
print("Task completed:%s"%task.done())

# Run the coroutine
el = asyncio.new_event_loop()
asyncio.set_event_loop(el)
asyncio.run(main(coro()))

Output:

[<frame at 0x10fdfedc0, file '/Users/kpji/getstack_suspend.py', line 7, code coro>]

Task completed:True