new_contents: import sys
  
  def grep(pat, filename):
  	lines = open(filename).readlines()
  	list = []
  	for i in lines:
  		if pat in i:
  			list.append(i)
  	return "".join(list)
  
  def main():
  	pat = sys.argv[1]
  	filename = sys.argv[2]
  	print grep(pat,filename)
  
  if __name__ == "__main__":
          main()
  
subject: Create grep.py