text: #!/usr/bin/python
  #coding:utf-8
  import socket,sys,re
  
  if len(sys.argv) !=2:
  	print('Modo de uso: python smtpuser.py 192.168.0.1')
  	sys.exit(0)
  else:
  	listing=open("lista.txt")
  	smtp = socket.socket(socket.AF_INET,socket.SOCK_STREAM)
  	smtp.connect((sys.argv[1],25))
  	banner = smtp.recv(1024)
  	print(banner)
  	for list in listing:
  		smtp = socket.socket(socket.AF_INET,socket.SOCK_STREAM)
  		smtp.connect((sys.argv[1],25))
  		banner = smtp.recv(1024)
  		smtp.send('VRFY '+list)
  		user = smtp.recv(1024)
  		if re.search("252",user):
  			print('Usuário Encontrado: '+user.strip("252 2.0.0"))
  