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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 Close(self):
 """Close and destroy the object. This is similar to Flush, but does not maintain object validity. Hence the object should not be interacted with after Close(). Raises: LockError: The lease for this object has expired. """

    if self.locked and self.CheckLease() == 0:
      raise LockError("Can not update lease that has already expired.")

    self._WriteAttributes()

    # Releasing this lock allows another thread to own it.
    if self.locked:
      self.transaction.Release()

    if self.parent:
      self.parent.Close()

    # Interacting with a closed object is a bug. We need to catch this ASAP so
    # we remove all mode permissions from this object.
    self.mode = ""