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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 _hn2db(self, hn):
        '''
        This will add a hostname for a hostname for an included domain or return an existing entry
        '''
        db = self.hn_db
        hn_found = False
        for k,v in db.items():
            if v == hn:  #the hostname is in the database
                ret_hn = k
                hn_found = True
        if hn_found:
            return ret_hn
        else:
            self.hostname_count += 1    #we have a new hostname, so we increment the counter to get the host ID number
            o_domain = self.root_domain
            for od,d in self.dn_db.items():
                if d in hn:
                    o_domain = od
            new_hn = "host%s.%s" % (self.hostname_count, o_domain)
            self.hn_db[new_hn] = hn

            return new_hn