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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 create_subnet_group(name, description, subnet_ids, tags=None,
                        region=None, key=None, keyid=None, profile=None):
    '''
    Create an RDS subnet group

    CLI example to create an RDS subnet group::

        salt myminion boto_rds.create_subnet_group my-subnet-group \
            "group description" '[subnet-12345678, subnet-87654321]' \
            region=us-east-1
    '''
    res = __salt__['boto_rds.subnet_group_exists'](name, tags, region, key,
                                                 keyid, profile)
    if res.get('exists'):
        return {'exists': bool(res)}

    try:
        conn = _get_conn(region=region, key=key, keyid=keyid, profile=profile)
        if not conn:
            return {'results': bool(conn)}

        taglist = _tag_doc(tags)
        rds = conn.create_db_subnet_group(DBSubnetGroupName=name,
                                          DBSubnetGroupDescription=description,
                                          SubnetIds=subnet_ids, Tags=taglist)

        return {'created': bool(rds)}
    except ClientError as e:
        return {'error': __utils__['boto3.get_error'](e)}