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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 is_subnet_present(self, subnet_addr):
 """Returns if a subnet is present. """

        try:
            subnet_list = self.neutronclient.list_subnets(body={})
            subnet_dat = subnet_list.get('subnets')
            for sub in subnet_dat:
                if sub.get('cidr') == subnet_addr:
                    return True
            return False
        except Exception as exc:
            LOG.error("Failed to list subnet %(sub)s, Exc %(exc)s",
                      {'sub': subnet_addr, 'exc': str(exc)})
            return False