rlock release(releases lock by decrementing its recursion level if the recursion level is zero after the decrementthe lock is reset to the unlocked state otherwisethe lock remains locked this function should only be called by the thread that currently owns the lock semaphore and bounded semaphore semaphore is synchronization primitive based on counter that' decremented by each acquire(call and incremented by each release(call if the counter ever reaches zerothe acquire(method blocks until some other thread calls release(semaphore([value]creates new semaphore value is the initial value for the counter if omittedthe counter is set to value of semaphore instancessupports the following methodss acquire([blocking]acquires the semaphore if the internal counter is larger than zero on entrythis method decrements it by and returns immediately if it' zerothis method blocks until another thread calls release(the blocking argument has the same behavior as described for lock and rlock objects release(releases semaphore by incrementing the internal counter by if the counter is zero and another thread is waitingthat thread is awakened if multiple threads are waitingonly one will be returned from its acquire(call the order in which threads are released is not deterministic boundedsemaphore([value]creates new semaphore value is the initial value for the counter if value is omittedthe counter is set to value of boundedsemaphore works exactly like semaphore except the number of release(operations cannot exceed the number of acquire(operations subtle difference between semaphore and mutex lock is that semaphore can be used for signaling for examplethe acquire(and release(methods can be called from different threads to communicate between producer and consumer threads produced threading semaphore( consumed threading semaphore( def producer()while trueconsumed acquire(produce_item(produced release(def consumer()while trueproduced acquire(item get_item(consumed release( lib fl ff