list - Python series writing issue -

i have code writing series in text file

bin = int("377731")  open('{0}/{0}.txt'.format(bin)) fine:     cc in fine , in range(1000):         name = cc[6:11]         tg = open('{0}/{1}.txt'.format(bin,name), 'a')         tg.write('{0}{1:03}'.format(cc,i))         tg.close() 

i wanted code write output this

    37773100000000     37773100000001     ... 

but when excute code output shows this

    37773100000     000     37773100000     001     ... 

why code writing ? error?

when iterate on fine (for cc in fine) line with line break, hence linebreak between cc , i.

if display it, see:

>>> cc '37773100000\n' 

you can trim line using:

cc = cc.strip()