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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 with_source(self, lease):
 """ Init with existing lease. :param lease: An existing Lease. :type lease: ~azure.eventprocessorhost.lease.Lease """

        self.partition_id = lease.partition_id
        self.epoch = lease.epoch
        self.owner = lease.owner
        self.token = lease.token
        self.event_processor_context = lease.event_processor_context