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It is potentially used by oslo, but too specific to be recommended for other projects cs(ddtfdd}|S)Nr?r@csLt|}|&|g|Ri|WdS1s>0YdSN)rBr+rrIrJZrw_lockrNrOrrrPFs  z/read_locked..decorator..wrapperrQrUrVr]rrWCs zread_locked..decoratorr#rNrXrYrrVr read_locked6s   r^cs8fdd}s|s|St|dkr0||dS|SdS)aAcquires & releases a write lock around call into decorated method. NOTE(harlowja): if no attribute name is provided then by default the attribute named '_lock' is looked for (this attribute is expected to be a :py:class:`.ReaderWriterLock` object) in the instance object this decorator is attached to. NOTE(paulius): This function is DEPRECATED and will be kept until the end of time. It is potentially used by oslo, but too specific to be recommended for other projects cs(ddtfdd}|S)Nr?r@csLt|}|&|g|Ri|WdS1s>0YdSr[)rBr3r\r]rrrPis  z0write_locked..decorator..wrapperrQrUrVr]rrWfs zwrite_locked..decoratorr#rNrXrYrrVr write_lockedYs   r_)r?rccs4|d}z|VW|r0|n|r.|0dS)aContext manager that attempts to acquire a lock without a timeout, and releases it on exit (if acquired). Args: lock: A lock to try to acquire. Returns: Whether the lock was acquired. # NOTE(harlowja): the keyword argument for 'blocking' does not work # in py2.x and only is fixed in py3.x (this adjustment is documented # and/or debated in http://bugs.python.org/issue10789); so we'll just # stick to the format that works in both (oddly the keyword argument # works in py2.x but only with reentrant locks). NOTE(paulius): This function is DEPRECATED and will be kept until the end of time. It is potentially used by oslo, but too specific to be recommended for other projects FN)acquirerelease)r?Z was_lockedrrrtry_lock|s  rb)r r=rSr8typingrZ fastenersrobjectrrZr^r_r>Lockrrbrrrrs  c7##