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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 set_stream(self):
 """ Sets the download streams """


        if not self.auth:
            raise AccessError("Please use the remote() method to set rsync authorization or use remote(public=True) for public data")
        elif not self.initial_stream.task:
            raise AccessError("No files to download.")
        else:
            self.stream = self.get_stream()
            self.stream.source = join(self.remote_base, 'sas') if self.remote_base and not self.public else join(self.remote_base, self.release) if self.release else self.remote_base
            self.stream.destination = join(self.base_dir, self.release) if self.public and self.release else self.base_dir
            self.stream.cli.env = {'RSYNC_PASSWORD': self.auth.password} if self.auth.ready() else None
            if self.stream.source and self.stream.destination:
                for task in self.initial_stream.task:
                    self.set_stream_task(task)
            ntask = len(self.stream.task)
            if self.stream.stream_count > ntask:
                if self.verbose:
                    print("SDSS_ACCESS> Reducing the number of streams from %r to %r, the number of download tasks." % (self.stream.stream_count, ntask))
                self.stream.stream_count = ntask
                self.stream.streamlet = self.stream.streamlet[:ntask]