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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 get_hosts_unfinished(self, scan_id):
 """ Get a list of finished hosts."""


        unfinished_hosts = list()
        for target in self.scans_table[scan_id]['finished_hosts']:
            unfinished_hosts.extend(target_str_to_list(target))
        for target in self.scans_table[scan_id]['finished_hosts']:
           for host in self.scans_table[scan_id]['finished_hosts'][target]:
               unfinished_hosts.remove(host)

        return unfinished_hosts