Trouble with ftplib uploading to an FTP server

[Sky Larking]

This bit of code is designed to get the external IP address and
hostname of a client , write it locally to a file, then upload to an
FTP server. It works locally( one can see the IP number and hostname
with a time stamp in /Users/admin/Documents) , but when the file is
opened on the server after it's FTP'ed , it's blank....I think my
issue is something with the way I am utilizing the ftplib commands...
I am pretty sure instead of FTPing the file, it's just creating a new
one with the same name and uploading that?

This script is running on some OS X 10.5 clients and reporting back to
an Ubuntu 8.04 server...I am using the version of python bundled with
10.5.x ( 2.5.1 )

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import os
import datetime
import ftplib
import urllib2


currdate = datetime.datetime.now()
formatdate = currdate.strftime("%m-%d-%Y %H%M")

def log():

    fqn = os.uname()[1]
    ext_ip = urllib2.urlopen('http://whatismyip.org').read()
    log = open ('/Users/admin/Documents/locatelog.txt','w')
    log.write(str("Asset: %s " % fqn))
    log.write(str("Checking in from IP#: %s" % ext_ip))
    smush = str(fqn +' @ ' + formatdate)
    os.rename('/Users/admin/Documents/locatelog.txt','/Users/admin/
Documents/%s.txt' %  smush )
    s = ftplib.FTP('10.7.1.71','username','password')
    fd = open('/Users/admin/Documents/%s.txt' % smush,'rb')
    s.storbinary("STOR %s.txt" % smush , fd)

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