import sys#filename = sys.argv[1]filename=raw_input()with open(filename,'rb') as hugefile:    chunksize =1000    readable=''    while hugefile:        start = hugefile.tell()        print "starting at:", start        file_block = ''        for _ in xrange(start, start+chunksize):            line = hugefile.next()            file_block = file_block + line            print 'file_block', type(file_block), file_block        readable = readable + file_block        stop = hugefile.tell()        print 'readable' ,type(readable), readable        print ' reading bytes from %s to %s' % (start, stop)        print ' read bytes total:',len(readable)