scraping a website that requires you to scroll down

I am trying to scrape this website here:

However, it requires that I scroll down in order to collect additional data. I have no idea how to scroll down using Beautiful soup or python. Does anybody here know how?

The code is a bit of a mess but here it is.

import scrapy
from scrapy.selector import Selector
from testtest.items import TesttestItem
import datetime
from selenium import webdriver
from bs4 import BeautifulSoup
from HTMLParser import HTMLParser
import re
import time

class MLStripper(HTMLParser):


class MySpider(scrapy.Spider):
        name = "A1Locker"

        def strip_tags(html):
            s = MLStripper()
            s.feed(html)
            return s.get_data()

     allowed_domains = ['https://www.a1lockerrental.com']
    start_urls = ['http://www.a1lockerrental.com/self-storage/mo/st-
 louis/4427-meramec-bottom-rd-facility/unit-sizes-prices#/units?
 category=all']

     def parse(self, response):

                 url='http://www.a1lockerrental.com/self-storage/mo/st-
louis/4427-meramec-bottom-rd-facility/unit-sizes-prices#/units?
category=Small'
                driver = webdriver.Firefox()
                driver.get(url)
                html = driver.page_source
                soup = BeautifulSoup(html, 'html.parser')
        url2='http://www.a1lockerrental.com/self-storage/mo/st-louis/4427-
meramec-bottom-rd-facility/unit-sizes-prices#/units?category=Medium'
        driver2 = webdriver.Firefox()
                driver2.get(url2)
                html2 = driver.page_source
                soup2 = BeautifulSoup(html2, 'html.parser')                
                #soup.append(soup2)
                #print soup
        items = []
        inside = "Indoor"
                outside = "Outdoor"
        inside_units = ["5 x 5", "5 x 10"]
        outside_units = ["10 x 15","5 x 15", "8 x 10","10 x 10","10 x 
20","10 x 25","10 x 30"]
        sizeTagz = soup.findAll('span',{"class":"sss-unit-size"})
        sizeTagz2 = soup2.findAll('span',{"class":"sss-unit-size"})
        #print soup.findAll('span',{"class":"sss-unit-size"})



        rateTagz = soup.findAll('p',{"class":"unit-special-offer"})


        specialTagz = soup.findAll('span',{"class":"unit-special-offer"})
        typesTagz = soup.findAll('div',{"class":"unit-info"},)

        rateTagz2 = soup2.findAll('p',{"class":"unit-special-offer"})


        specialTagz2 = soup2.findAll('span',{"class":"unit-special-offer"})
        typesTagz2 = soup2.findAll('div',{"class":"unit-info"},)
        yield {'date': datetime.datetime.now().strftime("%m-%d-%y"),
                'name': "A1Locker"
                   }
        size = []
        for n in range(len(sizeTagz)):
                    print len(rateTagz)
                    print len(typesTagz)

                    if "Outside" in (typesTagz[n]).get_text():



                            size.append(re.findall(r'\d+',
 (sizeTagz[n]).get_text()))
                            size.append(re.findall(r'\d+',
 (sizeTagz2[n]).get_text()))
                            print "logic hit"
                for i in range(len(size)):
                        yield {
                    #soup.findAll('p',{"class":"icon-bg"})
                    #'name': soup.find('strong', {'class':'high'}).text

                    'size': size[i]
                    #"special": (specialTagz[n]).get_text(),
                    #"rate": re.findall(r'\d+',(rateTagz[n]).get_text()),
                    #"size": i.css(".sss-unit-size::text").extract(),
                    #"types": "Outside"

    }
            driver.close()

The desired output of the code is to have it display the data collected from this webpage: http://www.a1lockerrental.com/self-storage/mo/st-louis/4427-meramec-bottom-rd-facility/unit-sizes-prices#/units?category=all

To do so would require being able to scroll down to view the rest of the data. At least that is how it would be done in my mind.

Thanks, DM123