Grep for big file

py_grep.py

# I found grep is very slow for big files, I made a simpe python version

import sys


def search(file_name, wants):
    with open(file_name, 'r') as file:
        for line in file:
            for w in wants:
                if w in line:
                    print line,



def main():
	if len(sys.argv) < 3:
		print "Usage: python py_grep.py file_name.log \"string1\" \"string2\" ..."
		return

	file_name = sys.argv[1]
	wants = sys.argv[2:]
	search(file_name, wants)

if __name__ == "__main__":
	main()