[Python] Execute commands over nested ssh connection

This is a followup of my previous post. I updated my code as per this post. but getting an exception when connecting to hostC

import os
import paramiko

def main():
try:
private_key = paramiko.RSAKey(filename="/home/hostA/.ssh/id_rsa")
ssh_client_b = connect_to_host("100.100.100.100", "hostB", private_key)
execute_command_over_ssh(ssh_client_b,
"uname")
execute_command_over_ssh(ssh_client,
"ls /home/hostB/")

# hostC is network reachable only from hostB
# below is where I'm stuck where I need to login to remote host hostC via SSH from hostB
# and transfer the same file/directory transferred previously to hostB from hostA
# Also, I would like to know how to issue command to execute in hostC and get back the result of it

ssh_client_c = connect_to_host_using_channel(ssh_client_b, "200.200.200.200", "100.100.100.100", "hostB", hostC")
execute_command_over_ssh(ssh_client_c,
"uname")
execute_command_over_ssh(ssh_client_c,
"ls /home/hostC/")

finally:
print("closing ssh client connection")
ssh_client_b.close()
ssh_client_c.close()

def connect_to_host(host_name, user_name, private_key):
try:
# Create object of SSHClient and
# connecting to SSH
ssh_client = paramiko.SSHClient()

# Adding new host key to the local
# HostKeys object(in case of missing)
# AutoAddPolicy for missing host key to be set before connection setup.
ssh_client.set_missing_host_key_policy(paramiko.AutoAddPolicy())

ssh_client.connect(host_name,
port = 22,
username = user_name,
pkey = private_key)
except:
ssh_client.close()

return ssh_client

def execute_command_over_ssh(ssh_client, command):
# below line command will actually
# execute in your remote machine
(stdin, stdout, stderr) = ssh_client.exec_command(command)

# redirecting all the output in cmd_output
# variable
cmd_output = stdout.read()
print('log printing: ', command, cmd_output)

def connect_to_host_using_channel(vm, dest_ip, channel_ip, channel_user_name, dest_user_name):
try:
vm_transport = vm.get_transport()
dest_addr = (dest_ip, 22)
local_addr = (channel_ip, 22)
vm_channel = vm_transport.open_channel("direct-tcpip", dest_addr, local_addr)

jhost = paramiko.SSHClient()
jhost.set_missing_host_key_policy(paramiko.AutoAddPolicy())
private_key = paramiko.RSAKey(filename = f"{channel_user_name}@{channel_ip}:/home/{channel_user_name}/.ssh/id_rsa")
jhost.connect(dest_ip, username = dest_user_name, pkey = private_key, sock = vm_channel)
except:
print(f"Error while connecting to {dest_user_name}")
jhost.close()

return jhost


Error

Traceback (most recent call last):
File "/home/hostA/test-repos/.venv/bin/test-framework", line 10, in <module>
sys.exit(main())
^^^^^^
File "/home/hostA/test-repos/src/test_framework/__init__.py", line 19, in main
execute_command_over_ssh(ssh_client_c,
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/hostA/test-repos/src/test_framework/__init__.py", line 52, in execute_command_over_ssh
(stdin, stdout, stderr) = ssh_client_c.exec_command(command)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/hostA/test-framework/.venv/lib/python3.12/site-packages/paramiko/client.py", line 558, in exec_command
chan = self._transport.open_session(timeout=timeout)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^
AttributeError: 'NoneType' object has no attribute 'open_session'

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