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Z&dS )0z0Support for tasks, coroutines and the scheduler.TaskFIRST_COMPLETEDFIRST_EXCEPTION
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_repr_info^ s zTask._repr_info)limitc C s t j| |S )a Return the list of stack frames for this task's coroutine.
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suspended. If the coroutine has completed successfully or was
cancelled, this returns an empty list. If the coroutine was
terminated by an exception, this returns the list of traceback
frames.
The frames are always ordered from oldest to newest.
The optional limit gives the maximum number of frames to
return; by default all available frames are returned. Its
meaning differs depending on whether a stack or a traceback is
returned: the newest frames of a stack are returned, but the
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)r Z_task_get_stack)r2 r; r r r get_stacka s zTask.get_stack)r; filec C s t j| ||S )an Print the stack or traceback for this task's coroutine.
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to sys.stderr.
)r Z_task_print_stack)r2 r; r= r r r print_stackx s zTask.print_stackc C s4 d| _ | j rdS | jdk r*| jj r*dS d| _dS )a Request that this task cancel itself.
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Unlike Future.cancel, this does not guarantee that the
task will be cancelled: the exception might be caught and
acted upon, delaying cancellation of the task or preventing
cancellation completely. The task may also return a value or
raise a different exception.
Immediately after this method is called, Task.cancelled() will
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j | j d } X d S ) Nz!_step(): already done: {!r}, {!r}F_asyncio_future_blockingz6Task {!r} got Future {!r} attached to a different loopz!Task cannot await on itself: {!r}z;yield was used instead of yield from in task {!r} with {!r}zIyield was used instead of yield from for generator in task {!r} with {!r}zTask got bad yield: {!r}) r? r& formatr-
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fddt| D } t| || E dH S )a Wait for the Futures and coroutines given by fs to complete.
The sequence futures must not be empty.
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done, pending = yield from asyncio.wait(fs)
Note: This does not raise TimeoutError! Futures that aren't done
when the timeout occurs are returned in the second set.
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r| j S | j | | j t j W d|j X dS )a Wait for the single Future or coroutine to complete, with timeout.
Coroutine will be wrapped in Task.
Returns result of the Future or coroutine. When a timeout occurs,
it cancels the task and raises TimeoutError. To avoid the task
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If the wait is cancelled, the task is also cancelled.
This function is a coroutine.
N)r )r r
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call_laterrj functoolspartialr rO r rD remove_done_callbackr@ r? rT TimeoutError)futr^ r rh timeout_handlecbr r r r A s,
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| qW ||fS )zeInternal helper for wait() and wait_for().
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zSet of Futures is empty.Nc s\ d8 dks6t ks6tkrX| j rX| j d k rXd k rFj j sXjd d S )Nr r )r r cancelled exceptionr@ r? rI )r` )counterr_ rr rh r r _on_completion| s z _wait.._on_completion) r& rk rl rj lenrO r@ re ro r? r1 )rg r^ r_ r rw r` r? pendingr )rv r_ rr rh r rf o s(
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qW r|dk rʈj||x ttD ] }| V qW dS )am Return an iterator whose values are coroutines.
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exceptions!) of the original Futures (or coroutines), in the order
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for f in as_completed(fs):
result = yield from f # The 'yield from' may raise.
# Use result.
If a timeout is specified, the 'yield from' will raise
TimeoutError when the timeout occurs before all Futures are done.
Note: The futures 'f' are not necessarily members of fs.
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z!as_completed.._on_timeoutc s6 sd S j | j| r2d k r2j d S )N)remover{ r@ )r` )r? rr r} r r rw s
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|E dH S |j X dS )z9Coroutine that completes after a given time (in seconds).r N)r r rk r rl r Z _set_result_unless_cancelledr@ )ZdelayrT r rU hr r r r s
c C s t jdtdd t| |dS )zWrap a coroutine in a future.
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a7 Return a future aggregating results from the given coroutines
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done successfully, the returned future's result is the list of
results (in the order of the original sequence, not necessarily
the order of results arrival). If *return_exceptions* is True,
exceptions in the tasks are treated the same as successful
results, and gathered in the result list; otherwise, the first
raised exception will be immediately propagated to the returned
future.
Cancellation: if the outer Future is cancelled, all children (that
have not completed yet) are also cancelled. If any child is
cancelled, this is treated as if it raised CancelledError --
the outer Future is *not* cancelled in this case. (This is to
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c s@ t | |d}|j r|S |j}|j fdd}|j| S )a= Wait for a future, shielding it from cancellation.
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res = yield from something()
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something(), the cancellation did not happen. But its caller is
still cancelled, so the yield-from expression still raises
CancelledError. Note: If something() is cancelled by other means
this will still cancel shield().
If you want to completely ignore cancellation (not recommended)
you can combine shield() with a try/except clause, as follows:
try:
res = yield from shield(something())
except CancelledError:
res = None
)r c s\ j r | j s| j d S | j r. j n*| j }|d k rJ j| n j| j d S )N)rt ru r@ rH rI rT )innerrS )r r r r s
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