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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 confirm_cw_log(self, account, region, vpcname):
 """Create a new CloudWatch log group based on the VPC Name if none exists. Returns `True` if succesful Args: account (:obj:`Account`):
 Account to create the log group in region (`str`):
 Region to create the log group in vpcname (`str`):
 Name of the VPC the log group is fow Returns: `bool` """

        try:
            cw = self.session.client('logs', region)
            token = None
            log_groups = []
            while True:
                result = cw.describe_log_groups() if not token else cw.describe_log_groups(nextToken=token)
                token = result.get('nextToken')
                log_groups.extend([x['logGroupName'] for x in result.get('logGroups', [])])

                if not token:
                    break

            if vpcname not in log_groups:
                cw.create_log_group(logGroupName=vpcname)

                cw_vpc = VPC.get(vpcname)
                cw_vpc.set_property('vpc_flow_logs_log_group', vpcname)

                self.log.info('Created log group {}/{}/{}'.format(account.account_name, region, vpcname))
                auditlog(
                    event='vpc_flow_logs.create_cw_log_group',
                    actor=self.ns,
                    data={
                        'account': account.account_name,
                        'region': region,
                        'log_group_name': vpcname,
                        'vpc': vpcname
                    }
                )
            return True

        except Exception:
            self.log.exception('Failed creating log group for {}/{}/{}.'.format(
                account,
                region, vpcname
            ))