paramiko non blocking example

paramiko_runner.py

import sys
import paramiko
import os
import select
import getpass
import time

rpi = {
    "username": getpass.getuser(),
    "hostname": "hostname.of.server.here"
}

command = "cd /path/to/folder/ && python test_worker.py"
ssh = paramiko.SSHClient()
ssh.load_system_host_keys()
ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy())
ssh.connect(**rpi)
ssh_stdin, ssh_stdout, ssh_stderr = ssh.exec_command(command)

def worker(stdout, stderr):

    # Wait for the command to terminate
    print("Status of worker is {}".format(stdout.channel.exit_status_ready()))
    while not stdout.channel.exit_status_ready():
        time.sleep(1)
        print("Status of worker is {}".format(stdout.channel.exit_status_ready()))
        if stdout.channel.recv_ready():
            # Only print data if there is data to read in the channel
            print("Worker stdout.channel.recv_ready: {}".format(stdout.channel.recv_ready()))
            rl, wl, xl = select.select([stdout.channel], [], [], 0.0)
            if len(rl) > 0:
                # Print data from stdout
                print("Output: {}".format(stdout.channel.recv(1024).decode("utf-8")))



print("Reading output from master")
worker(ssh_stdout, ssh_stderr)
print("Finished reading output from master")

test_worker.py

import time
import sys

i = 0

while True:
    time.sleep(5)
    i = i + 5
    print("At time {}".format(i))
    if i > 15:
        sys.exit(0)

I have a question, if these code is non-blocking example, when you invoke a shell and use it with send() a recv() instead of exec_command and stdout, is the shell that I have generated a blocking socket or a non-blocking socket? I'm very lost right now.