def init_frag_list(fragment_list, new_frag_list):
    """Adapt the original fragment list to fit the build function requirements

    Parameters
    ----------
    fragment_list : str, file or pathlib.Path
        The input fragment list.
    new_frag_list : str, file or pathlib.Path
        The output fragment list to be written.
    
    Returns
    -------
    i : int
        The number of records processed this way.
    """
    handle_frag_list = open(fragment_list, 'r')
    handle_new_frag_list = open(new_frag_list, 'w')
    handle_new_frag_list.write('%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\n' % (
        'id', 'chrom', 'start_pos', 'end_pos', 'size', 'gc_content',
        'accu_frag', 'frag_start', 'frag_end'))
    handle_frag_list.readline()
    i = 0
    while 1:
        line_frag = handle_frag_list.readline()
        if not line_frag:
            handle_frag_list.close()
            handle_new_frag_list.close()
            break
        i += 1
        data = line_frag.split('\t')
        id_init = data[0]
        contig_name = data[1]
        start_pos = data[2]
        end_pos = data[3]
        length_kb = data[4]
        gc_content = str(float(data[5]))
        accu_frag = str(1)
        frag_start = id_init
        frag_end = id_init
        handle_new_frag_list.write('%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\n' %
            (id_init, contig_name, start_pos, end_pos, length_kb,
            gc_content, accu_frag, frag_start, frag_end))
    return i
