gistfile1.py

domain_counts={}

for url in urls:
    # prime the dict if the domain isn't there
    if not domain_counts.get(domain):
        domain_counts = {}
    
    # split_your_url does not exist
    domain, path = split_your_url(url)
    
    # again, prime the child dict if the path isn't there
    if not domain_counts[domain].get(path):
        domain_counts[domain][path] = 0
    
    domain_counts[domain][path] += 1