fix bugs

def get_gtf_attribute(gtf_record, attribute):

    try:

        attr = re.search(f'{attribute} "(.+?)";', gtf_record[8]).group(1)

        attr = re.search(f'{attribute} "(.+?)"', gtf_record[8]).group(1)

    except AttributeError:

        raise ValueError(

            f'Could not parse attribute {attribute} '

            f'from GTF with feature type {record[2]}'

            f'from GTF with feature type {gtf_record[2]}'

        )

    return attr

        gene_to_locus_mapping = {}

    with open(gtf_fn) as gtf:

        for i, record in enumerate(gtf):

            if record.startswith('#'):

                continue

            record = record.split('\t')

            chrom, _, feat_type, start, end, _, strand = record[:7]

            start = int(start) - 1