Automating Telnet without spawn/expect/send commands - unix

I did ask this question before but that thread was closed as the question was vague. So here is try #2:
I wish to have a simple script that connects to a remote machine via telnet, then executes the command ZAHO, and then stores the output in a file cat.txt on my local machine. Here is the code I tried:
(echo "PPATIL"; sleep 1 ; echo "IDEA#2010" ; sleep 1;) |telnet 10.110.3.132 23<< EOF
ZAHO; > cat.txt
EOF
The following thing happens when I run the script:
Trying 10.110.3.132...
Connected to 10.110.3.132.
Escape character is '^]'
After this, I come back to my shell prompt without anything happening.
Now, even when I supply a wrong a password, I still get the same error.
P.S.: spawn/expect/send are not present and only option to login is through telnet.
I also tried this
(echo "PPATIL"; sleep 1 ; echo "IDEA#2010" ; sleep 1;echo "ZAHO;";) |telnet 10.110.3.132 23
In this case however, the remote machine gets connected, it shows me the username prompt, enters the username, then shows password prompt, then enters password, sleeps for a second and then appends "ZAHO;" to the password, and gets disconnected.
If I remove echo ZAHO; then also it gets disconnected after entering username and password.

In general:
cmd | cmd2 << EOF
EOF
is ill defined. (I'm not sure if the shell grammar clarifies this as undefined, or implementation defined, or what, but it certainly is not going to do what you want.) cmd2 can only have one input source, but you are trying to give it input both from the pipe and the heredoc. You need to pick one. Perhaps you can try:
{ cmd1; cat << EOF; } | cmd2
input
EOF
but that is pretty obfuscated, and you would be better off writing a script to generate the desired input.

If you are not restricted to shell script. Python has a
telnet interface in its standard library. Actually the example given on the library documentation page, is very close to what you want.
Python is perhaps not as ubiquitous as shell, but it is widely deployed and used.

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