Python Web Scrape Unknown Number of Pages - python-3.x

Question

I have working code that scrapes a single Craigslist page for specific information, but what would I need to add in order to grab the data from ALL of the pages (not knowing how many pages ahead of time)?
from urllib.request import urlopen as uReq
from bs4 import BeautifulSoup as soup
my_url="https://portland.craigslist.org/search/sss?query=electronics&sort=date"
uClient=uReq(my_url) #sends GET request to URL
page_html=uClient.read() #reads returned data and puts it in a variable
uClient.close() #close the connection
#create a file that we will want later to write parsed data to
filename="ScrapedData.csv"
f=open(filename, 'w')
headers="date, location, title, price\n"
f.write(headers)
#use BS to parse the webpage
page_soup=soup(page_html,'html.parser') #applying BS to the obtained html
containers=page_soup.findAll('p',{'class','result-info'})
for container in containers:
container_date=container.findAll('time',{'class','result-date'})
date=container_date[0].text
try:
container_location=container.findAll('span',{'class','result-hood'})
location=container_location[0].text
except:
try:
container_location=container.findAll('span',{'class','nearby'})
location=container_location[0].text
except:
location='NULL'
container_title=container.findAll('a',{'class','result-title'})
title=container_title[0].text
try:
container_price=container.findAll('span',{'class','result-price'})
price=container_price[0].text
except:
price='NULL'
#to print to screen
print('date:'+date)
print('location:'+location)
print('title:'+title)
print('price:'+price)
#to write to csv
f.write(date+','+location.replace(",","-")+','+title.replace(","," ")+','+price+'\n')
f.close()

Answer 1

Apart from what sir Andersson has already shown, you can do that as well for this site:
import requests
from bs4 import BeautifulSoup
import csv
page_link = "https://portland.craigslist.org/search/sss?s={}&query=electronics&sort=date"
for link in [page_link.format(page) for page in range(0,1147,120)]: #this is the fix
res = requests.get(link)
soup = BeautifulSoup(res.text,'lxml')
for container in soup.select('.result-info'):
try:
date = container.select('.result-date')[0].text
except IndexError:
date = ""
try:
title = container.select('.result-title')[0].text
except IndexError:
title = ""
try:
price = container.select('.result-price')[0].text
except IndexError:
price = ""
print(date,title,price)
with open("craigs_item.csv","a",newline="",encoding="utf-8") as outfile:
writer = csv.writer(outfile)
writer.writerow([date,title,price])

Answer 2

You can try to loop through all pages by handling "s" parameter in URL until you find page with no results (page with text "search and you will find"):
import requests
results_counter = 0
while True:
my_url="https://portland.craigslist.org/search/sss?query=electronics&sort=date&s=%d" % results_counter
page_html = requests.get(my_url).text
if "search and you will find" in page_html:
break
else:
results_counter += 120
filename="ScrapedData.csv"
f=open(filename, 'w')
headers="date, location, title, price\n"
f.write(headers)
page_soup=soup(page_html,'html.parser') #applying BS to the obtained html
containers=page_soup.findAll('p',{'class','result-info'})
...