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Paramiko equivalent of ssh host -t bash

In my Python3 script, I am trying to use Paramiko to ssh into remote devices. I can do that just fine. The issue is that ssh dumps me into a proprietary shell. I need to add -t bash to the .connect command to dump me into a bash shell. Here is what I have that is working:
ssh_tranfer = paramiko.SSHClient()
ssh_transfer.set_missing_host_key_policy(paramiko.AutoAddPolicy)
ssh.connect(hostname=device, port=22, username=username, key_filename=private_key_name)
With this I can connect just fine, but like I said, I am in the proprietary shell and can't pass it commands. I am not even sure that I can do it this way.
I define all the parameters that I am using (ie - device, username, and the private key) prior to the ssh.connect shown above.
If I was to ssh into the device directly from my computer to go straight to the bash shell, I would use:
ssh username#device.com -t bash
I would like to find a way to do this using paramiko.
Thanks for the help!

The -t + bash in ssh do two things:
Starts command bash in "exec" channel (instead of starting "shell" channel, what ssh does by default).
For that, see Python Paramiko - Run command
The -t forces an interactive session, what would be the default for "shell", but is by default disabled for "exec".
For that, pass get_pty=True to SSHClient.exec_command.
Obligatory warning: Do not use AutoAddPolicy this way – You are losing a protection against MITM attacks by doing so. For a correct solution, see Paramiko "Unknown Server".

using paramiko to start python script remotely, won't import user modules [duplicate]

I am trying to run sesu command in Unix server from Python with the help of Paramiko exec_command. However when I am running this command exec_command('sesu test'), I am getting
sh: sesu: not found
When I am running simple ls command it giving me desired output. Only with sesu command it is not working fine.
This is how my code looks like:
import paramiko
host = host
username = username
password = password
port = port
ssh=paramiko.SSHClient()
ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy())
ssh.connect(ip,port,username,password)
stdin,stdout,stderr=ssh.exec_command('sesu test')
stdin.write('Password')
stdin.flush()
outlines=stdout.readlines()
resp=''.join(outlines)
print(resp)

The SSHClient.exec_command by default does not run shell in "login" mode and does not allocate a pseudo terminal for the session. As a consequence a different set of startup scripts is (might be) sourced, than in your regular interactive SSH session (particularly for non-interactive sessions, .bash_profile is not sourced). And/or different branches in the scripts are taken, based on an absence/presence of TERM environment variable.
Possible solutions (in preference order):
Fix the command not to rely on a specific environment. Use a full path to sesu in the command. E.g.:
/bin/sesu test
If you do not know the full path, on common *nix systems, you can use which sesu command in your interactive SSH session.
Fix your startup scripts to set the PATH the same for both interactive and non-interactive sessions.
Try running the script explicitly via login shell (use --login switch with common *nix shells):
bash --login -c "sesu test"
If the command itself relies on a specific environment setup and you cannot fix the startup scripts, you can change the environment in the command itself. Syntax for that depends on the remote system and/or the shell. In common *nix systems, this works:
PATH="$PATH;/path/to/sesu" && sesu test
Another (not recommended) approach is to force the pseudo terminal allocation for the "exec" channel using the get_pty parameter:
stdin,stdout,stderr = ssh.exec_command('sesu test', get_pty=True)
Using the pseudo terminal to automate a command execution can bring you nasty side effects. See for example Is there a simple way to get rid of junk values that come when you SSH using Python's Paramiko library and fetch output from CLI of a remote machine?
You may have a similar problem with LD_LIBRARY_PATH and locating shared objects.
See also:
Environment variable differences when using Paramiko
Certain Unix commands fail with "... not found", when executed through Java using JSch

Combining interactive shell and recv_exit_status method using Paramiko

I am using paramiko for SSH with my remote devices.
and I am make communication with them using paramiko shell (invoke_shell() method) for interactivity.
The main problem with paramiko shell (as I've read in many answers here) is that there is no guarantee that paramiko SSHClient methods which indicates that the server finished writing such as recv_exit_status() and exit_status_ready() will behave as expected.
So I created mechanism that will read the last line of the output from the shell and determine if this line contains only shell's prompt in such case the command execution was finished.
This is works in case there is no changes in prompt.
Now I've read here Wait until task is completed on Remote Machine through Python that 'exec_command()' method return tuple 'stdin, stdout, stderr' and preforming stdout.channel.recv_exit_status() will block channel until it is done.
My question is if I will create such a tuple and will preform stdout.channel.recv_exit_status() with stdout that I will get when I am open on each interactive command (meaning I will do 'shell_chan.send('something')' and then will do stdout.channel.recv_exit_status()) will it do the job? will it return only when interactive command has finished?

SSHClient.recv_exit_status signals that the channel has closed.
The "shell" channel closes only when the shell closes. A "shell" is a black box with input and output. Nothing else. There's no way SSH, let alone Paramiko, will be able to tell anyhow, when individual commands in the shell have finished. The shell_chan.send('something') is not a signal to SSH to execute a command. It simply sends an arbitrary input to the "shell". Nothing else. It's totally at the shell disposition how the input is interpreted. All that the SSH/Paramiko gets back is an arbitrary unstructured output. Paramiko cannot interpret it anyhow for you.
If you need to be able to tell when a command has finished, you need to use "exec" channel (SSHClient.exec_command method in Paramiko). You should not use the "shell" channel, unless you are implementing an interactive SSH terminal client, like PuTTY (or in rare cases, when you talk to an limited SSH server that does not implement the "exec" channel, as it often the case with dedicated devices, such as routers, switches, etc).
For related questions, see:
Execute multiple dependent commands individually with Paramiko and find out when each command finishes
How to get each dependent command execution output using Paramiko exec_command
Use the same SSH object to issue "exec_command()" multiple times in Paramiko
Execute (sub)commands in secondary shell/command on SSH server in Paramiko
Invoke multiple commands inside a process in interactive ssh mode
Executing command using Paramiko exec_command on device is not working
What is the difference between exec_command and send with invoke_shell() on Paramiko?

Identical command sent over paramiko and ssh works over ssh but not paramiko [duplicate]

I am connecting to SSH via terminal (on Mac) and run a Paramiko Python script and for some reason, the two sessions seem to behave differently. The PATH environment variable is different in these cases.
This is the code I run:
import paramiko
ssh = paramiko.SSHClient()
ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy())
ssh.connect('host', username='myuser',password='mypass')
stdin, stdout, stderr =ssh.exec_command('echo $PATH')
print (stdout.readlines())
Any idea why the environment variables are different?
And how can I fix it?

The SSHClient.exec_command by default does not allocate a pseudo terminal for the session. As a consequence a different set of startup scripts is (might be) sourced (particularly for non-interactive sessions, .bash_profile is not sourced). And/or different branches in the scripts are taken, based on an absence/presence of TERM environment variable.
To emulate the default Paramiko behavior with the ssh, use the -T switch:
ssh -T myuser#host
See the ssh man:
-T Disable pseudo-tty allocation.
Contrary, to emulate the default ssh behavior with Paramiko, set the get_pty parameter of the exec_command to True:
def exec_command(self, command, bufsize=-1, timeout=None, get_pty=False):
Though rather than working around the issue by allocating the pseudo terminal in Paramiko, you should better fix your startup scripts to set the same PATH for all sessions.
For that see Some Unix commands fail with "<command> not found", when executed using Python Paramiko exec_command.

Working with the Channel object instead of the SSHClient object solved my problem.
chan=ssh.invoke_shell()
chan.send('echo $PATH\n')
print (chan.recv(1024))
For more details, see the documentation

Using paramiko when a unix server is using VShell

Use case
On a unix server , when login manually ,opens a command shell of its own to run the command.
I am trying to automate this by using paramiko , however , somehow i am not able to execute the command on command shell using paramiko
What i have done ?
I created a simple script which is able to make connection, but its not executing command on Vshell as the ouput is always coming empty.
import paramiko
import sys
ssh_client=paramiko.SSHClient()
ssh_client.set_missing_host_key_policy(paramiko.AutoAddPolicy())
ssh_client.connect(hostname=sys.argv[1],port=sys.argv[2],username=sys.argv[3],password=sys.argv[4])
command="show hwid"
stdin,stdout,stderr=ssh_client.exec_command(command)
out=stdout.read()
print out
err=stderr.read()
print err
ssh_client.close()
The same script runs perfectly fine , when its used on server where vshell is not being used
Anyhelp or suggestion on this?

stdin,stdout,stderr=ssh_client.exec_command(command)
Regarding this line of code, I suspect that the SSH server is not properly configured to allow commands to be executed in this way (this is the equivalent of ssh myserver show hwid, rather than typing it into the terminal after login).
You might want to imitate the behaviour of typing the command in after logging into the server, and for that I think this is appropriate:
shell = ssh_client.invoke_shell()
stdin, stdout, stderr = shell.exec_command(command)