I don't see why not.
Here is something with a little more detail:
try:
f = FileWrapper(buf, len(buf))
cmd = "STOR " + fname
ftp = FTP(ftpserver)
# uncomment for debug
ftp.set_debuglevel(2)
ftp.set_pasv('true')
ftp.login(ftpuser, ftppwd)
ftp.cwd(ftpdir)
ftp.storbinary(cmd, f)
ftp.quit()
ret = True