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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def flock(path):
 """Attempt to acquire a POSIX file lock. """

    with open(path, "w+") as lf:
        try:
            fcntl.flock(lf, fcntl.LOCK_EX | fcntl.LOCK_NB)
            acquired = True
            yield acquired

        except OSError:
            acquired = False
            yield acquired

        finally:
            if acquired:
                fcntl.flock(lf, fcntl.LOCK_UN)