Executing su user (without password) on paramiko ssh connection
Each exec_command() call happens in a new shell, so there is no state carried over from previous commands. If commands rely on a previous command to execute, you have to send them in a single statement, or as a script. If you want an interactive shell, there is the invoke_shell command, but then you need to parse the shell output to simulate interactive use (the pexpect library can be used here).
You can use the sudo command, or su -c to execute the command.. However, I would suggest configuring a secure login for the needed user, and connecting as that user directly.