BS4 | Python Fiddle

from bs4 import BeautifulSoup
import urllib2
wiki ="http://en.wikipedia.org/wiki/List_of_postcode_districts_in_the_United_Kingdom"
header = {'User-Agent': 'Mozilla/5.0'} #Needed to prevent 403 error on Wikipedia
req = urllib2.Request(wiki,headers=header)
page = urllib2.urlopen(req)
soup = BeautifulSoup(page)
area = ""
district = ""
town = ""
county = ""
table = soup.find("table", { "class" : "wikitable sortable" })
f = open('output.csv', 'w')
for row in table.findAll("tr"):
cells = row.findAll("td")
#For each "tr", assign each "td" to a variable.
if len(cells) == 4:
area = cells[0].find(text=True)
district = cells[1].findAll(text=True)
town = cells[2].find(text=True)
county = cells[3].find(text=True)
#district can be a list of lists, so we want to iterate through the top level lists first...
for x in range(len(district)):
#For each list, split the string
postcode_list = district[x].split(",")
#For each item in the split list...
for i in range(len(postcode_list)):
#Check it's a postcode and not other text
if (len(postcode_list[i]) > 2) and (len(postcode_list[i]) <= 5):
#Strip out the "\n" that seems to be at the start of some postcodes
write_to_file = area + "," + postcode_list[i].lstrip('\n').strip() + "," + town +"," + county + "\n"
print write_to_file
f.write(write_to_file)
f.close()

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