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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 unlock(self):

 """
 Release this lock.
 
 This deletes the directory with the given name.
 
 @raise: Any exception os.readlink() may raise, or
 ValueError if the lock is not owned by this process.
 """

        pid = readlink(self.name)
        if int(pid) != os.getpid():
            raise ValueError("Lock %r not owned by this process" % (self.name,))
        rmlink(self.name)
        self.locked = False