Tensorboard Error - NameError: name 'tensorboard' is not defined - tensorboard

Question

I am now learning tensorflow but am unable to get tensorboard to work. I tried the simple program below with no luck. The program works before I use the tensorboard code but when I use the tensorboard code I get the following error:
NameError: name 'tensorboard' is not defined
Please any assistance is apppreciated.
import tensorflow as tf
a = tf.constant(5, name="input_a")
b = tf.constant(3, name="input_a")
c = tf.multiply(a,b, name="mul_c")
d = tf.add(a,b, name="add_d")
e = tf.add(c,d, name="add_e")
sess = tf.Session()
sess.run(e)
output = sess.run(e)
writer = tf.summary.FileWriter('/tmp/newtest', graph=sess.graph)
print(sess.run(e))
tensorboard --logdir /tmp/newtest

Answer 1

I believe this is already 'answered', but, to give a sample of what I did, regarding this, and I hope it helps you or others.
This is just covering ending overhead of triggering & showing tensorboard.
import subprocess
import webbrowser
import time
logLocation = 'tflearn_logs'
print("\r\nWould you like to see the visual results (y/N)? ", end='', flush=True)
answer = input()
if answer.strip().lower() == "y":
port = str(8018)
print("Starting Tensorboard to visualize... ")
process = subprocess.Popen(['tensorboard', "--logdir='" + logLocation + "'", '--port=' + port])
# Wait for a few seconds, give the tensorboard a headstart
time.sleep(5)
print("Opening Tensorboard webpage... ")
url = 'http://127.0.0.1:' + port + '/'
# Path differs per OS (Windows, Linux, iOS)
chrome_path = 'C:/Program Files (x86)/Google/Chrome/Application/chrome.exe %s'
webbrowser.get(chrome_path).open(url)
print("Press enter to quit... ", end='', flush=True)
answer = input()
if process is not None:
process.kill()