How do i set up proxy in selenium?

I have been trying to implement proxy to my selenium webdriver. Have no idea what's wrong with my code. Any idea?

import os
from selenium import webdriver
def open_browser():
    chromeUrl= "C:/Users/Drivers/chromedriver.exe"
    firefoxUrl= "C:/Users/Drivers/geckodriver.exe"
    edgeUrl="C:/Users/Drivers/MicrosoftWebDriver.exe"
    print("Starting opening web browser")
    try:
        f= open('saved/proxy.txt','r')  
        proxy_ip = f.read()
        f.close()
        PROXY= proxy_ip
        print("I have download a proxy: " + PROXY)


        if len(proxy_ip) <= 1:
            print("No Proxy will be used...")
            driver = webdriver.Firefox(executable_path= firefoxUrl)

        else:
             webdriver.DesiredCapabilities.Edge['proxy'] = {
            "httpProxy":PROXY,
            "ftpProxy":PROXY,
            "sslProxy":PROXY,
            "noProxy":None,
            "proxyType":"MANUAL",
            "class":"org.openqa.selenium.Proxy",
            "autodetect":False}
            driver = webdriver.Remote("http://localhost:4444/wd/hub", webdriver.DesiredCapabilities.Edge(EdgeUrl))




    except:
        os.system("python proxy_request.py")
        print("Warning: No proxy")
        driver = webdriver.Edge(executable_path= "C:/Users/Drivers/MicrosoftWebDriver.exe")
    driver.implicitly_wait(10)
    driver.set_page_load_timeout(300)
    return driver
driver = open_browser()
url = 'htttp://www.google.com'
driver.get(url)

I couldn't deal with the problem. Half of the code in from official webdriver documentation, although i couldn't find one for EDGE.