Loop through payload Python - python-2.7

Question

There is a site that i connect to, but need to login 4 times with different user names and passwords.
Is there anyway that i can do this by looping through the usernames and passwords in a payload.
This is the first time im am doing this and am not really sure of how to go about it.
The code works fine if i post just one username and password.
Im using Python 2.7 and BeautifulSoup and requests.
Here is my code.
import requests
import zipfile, StringIO
from bs4 import BeautifulSoup
# Here were add the login details to be submitted to the login form.
payload = [
{'USERNAME': 'xxxxxx','PASSWORD': 'xxxxxx','option': 'login'},
{'USERNAME': 'xxxxxx','PASSWORD': 'xxxxxxx','option': 'login'},
{'USERNAME': 'xxxxx','PASSWORD': 'xxxxx','option': 'login'},
{'USERNAME': 'xxxxxx','PASSWORD': 'xxxxxx','option': 'login'},
]
#Possibly need headers later.
headers = {'user-agent': 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_12_5) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/59.0.3071.115 Safari/537.36'}
base_url = "https://service.rl360.com/scripts/customer.cgi/SC/servicing/"
with requests.Session() as s:
p = s.post('https://service.rl360.com/scripts/customer.cgi?option=login', data=payload)
# Get the download page to scrape.
r = s.get('https://service.rl360.com/scripts/customer.cgi/SC/servicing/downloads.php?Folder=DataDownloads&SortField=ExpiryDays&SortOrder=Ascending', stream=True)
content = r.text
soup = BeautifulSoup(content, 'lxml')
#Now i get the most recent download URL.
download_url = soup.find_all("a", {'class':'tabletd'})[-1]['href']
#now we join the base url with the download url.
download_docs = s.get(base_url + download_url, stream=True)
print "Checking Content"
content_type = download_docs.headers['content-type']
print content_type
print "Checking Filename"
content_name = download_docs.headers['content-disposition']
print content_name
print "Checking Download Size"
content_size = download_docs.headers['content-length']
print content_size
#This is where we extract and download the specified xml files.
z = zipfile.ZipFile(StringIO.StringIO(download_docs.content))
print "---------------------------------"
print "Downloading........."
#Now we save the files to the specified location.
z.extractall('C:\Temp')
print "Download Complete"

Answer 1

Just use a for loop. You may need to adjust your download directory if files will be overwritten.
payloads = [
{'USERNAME': 'xxxxxx1','PASSWORD': 'xxxxxx','option': 'login'},
{'USERNAME': 'xxxxxx2','PASSWORD': 'xxxxxxx','option': 'login'},
{'USERNAME': 'xxxxx3','PASSWORD': 'xxxxx','option': 'login'},
{'USERNAME': 'xxxxxx4','PASSWORD': 'xxxxxx','option': 'login'},
]
....
for payload in payloads:
with requests.Session() as s:
p = s.post('https://service.rl360.com/scripts/customer.cgi?option=login', data=payload)
...