Using Python, how can I search through a list of URLs and determine which websites have the Facebook Pixel?

Beginner at Python here, this question is long but it's simple I promise.

I'm scraping the webpages of a list of URLs for all kinds of data and making spreadsheets to search for trends. The one thing I cannot figure out is how to target is the presence of a Facebook pixel. The sites that I'm pulling data from are all Shopify sites, so the pixel exists in the source code under a script like this:

<script class="analytics" type="text/javascript">

    (function () {
      var customDocumentWrite = function(content) {
        var jquery = null;

        if (window.jQuery) {
          jquery = window.jQuery;
        } else if (window.Checkout && window.Checkout.$) {
          jquery = window.Checkout.$;
        }

        if (jquery) {
          jquery('body').append(content);
        }
      };

      var trekkie = window.ShopifyAnalytics.lib = window.trekkie = window.trekkie || [];
      if (trekkie.integrations) {
        return;
      }
      trekkie.methods = [
        'identify',
        'page',
        'ready',
        'track',
        'trackForm',
        'trackLink'
      ];
      trekkie.factory = function(method) {
        return function() {
          var args = Array.prototype.slice.call(arguments);
          args.unshift(method);
          trekkie.push(args);
          return trekkie;
        };
      };
      for (var i = 0; i < trekkie.methods.length; i++) {
        var key = trekkie.methods[i];
        trekkie[key] = trekkie.factory(key);
      }
      trekkie.load = function(config) {
        trekkie.config = config;
        var script = document.createElement('script');
        script.type = 'text/javascript';
        script.onerror = function(e) {
          (new Image()).src = '//v.shopify.com/internal_errors/track?error=trekkie_load';
        };
        script.async = true;
        script.src = 'http://ift.tt/2wzmuPS';
        var first = document.getElementsByTagName('script')[0];
        first.parentNode.insertBefore(script, first);
      };
      trekkie.load(
        {"Trekkie":{"appName":"storefront","development":false,"defaultAttributes":{"shopId":21353283,"isMerchantRequest":null,"themeId":177557972,"themeCityHash":9027251861051819334}},"Performance":{"navigationTimingApiMeasurementsEnabled":true,"navigationTimingApiMeasurementsSampleRate":0.1},"Facebook Pixel":{"pixelIds":["1930018160600140"],"agent":"plshopify1.2"},"Session Attribution":{}}
      );

      var loaded = false;
      trekkie.ready(function() {
        if (loaded) return;
        loaded = true;

        window.ShopifyAnalytics.lib = window.trekkie;


        var originalDocumentWrite = document.write;
        document.write = customDocumentWrite;
        try { window.ShopifyAnalytics.merchantGoogleAnalytics.call(this); } catch(error) {};
        document.write = originalDocumentWrite;


    window.ShopifyAnalytics.lib.page(
      null,
      {"pageType":"home"}
    );


      });


  var eventsListenerScript = document.createElement('script');
  eventsListenerScript.async = true;
  eventsListenerScript.src = "//cdn.shopify.com/s/assets/shop_events_listener-4c5801cae3452eff0ededa0ac07d432c1240b78b7e11282cceb3c3213951104b.js";
  document.getElementsByTagName('head')[0].appendChild(eventsListenerScript);

    })();
  </script>

The nice thing about scraping Shopify sites is that they are, for the most part, uniform. If a site is using a FB pixel it will appear in this segment of the code pasted above:

 trekkie.load(
        {"Trekkie":{"appName":"storefront","development":false,"defaultAttributes":{"shopId":21353283,"isMerchantRequest":null,"themeId":177557972,"themeCityHash":9027251861051819334}},"Performance":{"navigationTimingApiMeasurementsEnabled":true,"navigationTimingApiMeasurementsSampleRate":0.1},"Facebook Pixel":{"pixelIds":["1930018160600140"],"agent":"plshopify1.2"},"Session Attribution":{}}
      );

So, I need to make it so that "Yes" appears in my spreadsheet column if the source code of the page contains the word "Facebook Pixel". My code basically looks like this:

from urllib.request import urlopen as uReq
from bs4 import BeautifulSoup as soup

my_url = 'www.example.com'

uClient = uReq(my_url)

page_html = uClient.read()

uClient.close()

page_soup = soup(page_html, "html.parser")

containers = page_soup.findAll("div",{"class":"item-container"})
container = containers[0]

filename = "web_scrape.csv"
f = open(filename, "w")

headers = "brand, product_name, shipping\n"


f.write(headers)

for container in containers:
    brand = container.div.div.a.img["title"]

    title_container = container.findAll("a", {"class":"item-title"})
    product_name = title_container[0].text


    shipping_container = container.findAll("li", {"class":"price-ship"})
    shipping = shipping_container[0].text.strip()

    print("brand: " + brand)
    print("product_name: " + product_name)
    print("shipping: " + shipping)

    f.write(brand + "," + product_name.replace(",", "|") + ","+ shipping + "\n")

f.close()