Set column number of CSV file to column number of first row moving latter items

fixcsv.py

import sys
import itertools
import csv

def grouper(n, iterable, fillvalue=None):
    "grouper(3, 'ABCDEFG', 'x') --> ABC DEF Gxx"
    args = [iter(iterable)] * n
    return itertools.izip_longest(fillvalue=fillvalue, *args)

def chainfix(lines):
    for line in lines:
        fix = line
        if not line[0]:
            fix = line[1:]
        for item in fix:
            yield item

def skip_empty(items):
    last = ''
    for i in items:
        if i.startswith(';') and i.endswith(';') and len(i) > 1:
            yield i
        elif i.startswith(';'):
            nextitem = next(items)
            if nextitem:
                yield i + ';'
                if nextitem != ';':
                    yield nextitem
            else:
                last = i
        elif i == ';' and last:
            yield last + ';'
            last = ''

def fixlines(lines):
    columns = tuple(s.strip(';') for s in next(lines, []))
    chained = (s.strip(';') for s in skip_empty(itertools.chain(*lines)))
    # chained = chainfix(lines)
    return itertools.chain([columns], grouper(len(columns), chained))

def main(filename):
    with open(filename) as fp:
        lines = csv.reader(fp.readlines())
        fix = fixlines(lines)
        writer = csv.writer(sys.stdout, lineterminator='\n')
        writer.writerows(fix)
        return 0

if __name__ == '__main__':
    try:
        if len(sys.argv) > 1:
            sys.exit(main(sys.argv[1]))
        else:
            sys.stderr.write('usage: csvfix.py CSVFILE\n')
    except IOError as e:
        sys.stderr.write(str(e) + '\n')
    sys.exit(1)