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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 create_session(self, lock_type=library.LockType.shared, session=None):
 """Lock this machine Arguments: lock_type - see IMachine.lock_machine for details session - optionally define a session object to lock this machine against. If not defined, a new ISession object is created to lock against return an ISession object """

        if session is None:
            session = library.ISession()
        # NOTE: The following hack handles the issue of unknown machine state.
        #       This occurs most frequently when a machine is powered off and
        #       in spite waiting for the completion event to end, the state of
        #       machine still raises the following Error:
        #          virtualbox.library.VBoxErrorVmError: 0x80bb0003 (Failed to \
        #          get a console object from the direct session (Unknown \
        #          Status 0x80BB0002))
        error = None
        for _ in range(10):
            try:
                self.lock_machine(session, lock_type)
            except Exception as exc:
                error = exc
                time.sleep(1)
                continue
            else:
                break
        else:
            if error is not None:
                raise Exception("Failed to create clone - %s" % error)
        return session