PhantomJS python issue - python-3.x

Question

My python selenium tests are working on firefox dirver (GUI) without any issue. But i wanted to run my tests in headless mode. When i try to run the same script with headless mode (with few modifications). it gives wierd errors.
Ex:
selenium.common.exceptions.NoSuchElementException: Message{"errorMessage":"Unable to find element with id 'ext-gen1499
python script :
import os
import time
from selenium.webdriver.common.proxy import *
from selenium.webdriver.common.by import By
phantomjs_path=r"/home/xxxx/nodejs-installs/phantomjs-2.1.1-linux-x86_64/bin/phantomjs"
from selenium import webdriver
from selenium.webdriver.common.keys import Keys
from selenium.webdriver.support.ui import WebDriverWait
from selenium.webdriver.support import expected_conditions as EC
from selenium.webdriver.common.by import By
from selenium.common.exceptions import TimeoutException
from selenium.webdriver.firefox.firefox_binary import FirefoxBinary
service_args = ['--proxy=x.x.x.x:80','--proxy-type=https']
driver = webdriver.PhantomJS(executable_path=r'/home/xxxx/nodejs-installs/phantomjs-2.1.1-linux-x86_64/bin/phantomjs',service_args=service_args)
os.environ['MOZ_HEADLESS'] = '1'
driver.get("https://aaaaa.com")
def Login():
try:
driver.find_element_by_id("username").send_keys("test#aaaa.com")
driver.find_element_by_id("password").send_keys("xxxxxxx")
driver.find_element_by_id("Submit").click()
login_flag=1
except:
print("Error Loading Login page")
login_flag=0
finally:
return login_flag
def CreateMail():
try:
element = WebDriverWait(driver, 3).until(EC.presence_of_element_located((By.ID, "button-1143-btnInnerEl")))
driver.find_element_by_id("button-1143-btnInnerEl").click()
except TimeoutException:
print ("Loading took too much time - Create New Mail")
driver.find_element_by_id("ext-gen1499").send_keys("test#test.com")
driver.find_element_by_id("textfield-1265-inputEl").send_keys("Automated Test Mail from Selenium")
driver.find_element_by_id("button-1252-btnIconEl").click()
Am i missing anything ?

Answer 1

It is a good practice to add an implicit wait of at-least 10 seconds , for allowing the target page element/s to load completely.
driver.implicitly_wait(10)