Python: Help with counters and writing files [duplicate]

Answer 1

Hypothetical example.

import os
counter_file="counter.file"
if not os.path.exists(counter_file):
    open(counter_file).write("1");
else:
    num=int(open(counter_file).read().strip()) #read the number
# do processing...
outfile=open("out_file_"+str(num),"w")
for line in open("file_to_process"):
    # ...processing ...
    outfile.write(line)    
outfile.close()
num+=1 #increment
open(counter_file,"w").write(str(num))