from bs4 import BeautifulSoup as bs

filedata = open('bymarket.xml')

cont = bs(filedata, 'lxml')

course = cont.find('venue')
print(course.text)
container = cont.find('runners')
item = container.find_all('runnernode')
for horse in item:
    runner = horse.find('runnername').text
    odds = horse.find('availabletolay').find('price').text
    print(runner, odds)