code: def unlock(self):
          
          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
docs: 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.