Get information from a file based on a regexp and outputs to another file

getinfo.py

import sys 
import re

if __name__ == "__main__":

	file=sys.argv[1] #get the pointer to file
	rfp = open(file,"r") #file to be searched on
	ofp = open('results.txt',"w") #open a file to print results
	
	for lines in rfp:
		a = re.findall(";",lines)
		if (len(a) == 0):
			print lines,
			ofp.write(lines)