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r� Y n X ej ZZ dS )z.A Future class similar to the one in PEP 3148.)�Future� wrap_future�isfuture� N� )� base_futures)�events)�
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- Callbacks registered with add_done_callback() are always called
via the event loop's call_soon().
- This class is not compatible with the wait() and as_completed()
methods in the concurrent.futures package.
(In Python 3.4 or later we may be able to unify the implementations.)
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zFuture.exceptionr4 c C sB | j tkr | jj|| |d� n |dkr.t�� }| j�||f� dS )z�Add a callback to be run when the future becomes done.
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�zFuture.remove_done_callbackc C s8 | j tkr t�| j � d| ����|| _t| _ | �� dS )z�Mark the future done and set its result.
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rZ c C s | � � r dS | �|� dS )z?Helper setting the result only if the future was not cancelled.N)r8 rJ )rY r> r r r � _set_result_unless_cancelled s r[ c C sX t | �}|tjjkr tj| j� S |tjjkr8tj| j� S |tjjkrPtj| j� S | S d S r( )rL �
concurrent�futuresr: r �args� TimeoutErrorr< )r% Z exc_classr r r �_convert_future_exc# s r` c C sR |� � r| �� | �� s dS |�� }|dk r<| �t|�� n|�� }| �|� dS )z8Copy state from a future to a concurrent.futures.Future.N)r8 r3 Z set_running_or_notify_cancelr! rO r` r> rJ )r\ �sourcer! r> r r r � _set_concurrent_future_state/ s rb c C sT |� � r dS | � � r |�� n2| �� }|dk r>|�t|�� n| �� }|�|� dS )zqInternal helper to copy state from another Future.
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rd c s� t ��s t�tjj�s td��t ��s._set_statec s2 | � � r.�d ks�� kr"��� n ���j� d S r( )r8 r3 �call_soon_threadsafe)� destination)� dest_loopra � source_loopr r �_call_check_cancelh s
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