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� Zdd� Zdd� Zdd� Zdd� Zdd� Zdd�dd�Z z ddl Z W n e y� Y n 0 e j ZZ dS )z.A Future class similar to the one in PEP 3148.)�Future� wrap_future�isfuture� N)� GenericAlias� )� base_futures)�events)�
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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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