Given list of entries "hits, domain", determine the total hits of each subdomain

hit_counts.py

// Given a list of strings (int, string) where int is the number of hits and the string is a domain name,
// tally a domain and each of its subdomains' total hits. 

hit_list = ["100,yahoo.com",
           "20,mail.yahoo.com"]

def calculate_domain_hits():
    domain_counts = {}
    for entry in hit_list:
        # Parse each input entry
        entry_list = entry.split(',')
        domain = entry_list[1]
        hits = int(entry_list[0])
        # Let's bootstrap the domain so we can start looking at each part
        d_list = domain.split('.')
        for i in range(0, len(d_list)):
            # Join what we need and use it as our key
            cur_domain = '.'.join(d_list[i:])
            if cur_domain in domain_counts:
                domain_counts[cur_domain] = domain_counts[cur_domain] + hits
            else:
                domain_counts[cur_domain] = hits
    return domain_counts