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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 start_transfer(self):
        ''' pass the transfer spec to the Aspera sdk and start the transfer '''
        try:
            if not self.is_done():
                faspmanager2.startTransfer(self.get_transfer_id(),
                                           None,
                                           self.get_transfer_spec(),
                                           self)
        except Exception as ex:
            self.notify_exception(ex)