Группировать значения словаря по ключам

import requests
 
ips = ['129.203.29.198', '148.187.4.164','239.202.246.184','245.184.161.17','179.83.187.56','101.159.154.180','127.153.44.165',
'31.6.213.69','175.72.176.94','131.113.160.111','98.70.55.74']
 
for i in  ips:
 
    response = requests.get('http://freegeoip.net/json/' + i)
 
    country = (response.json().get('country_name'))
 
    i = list(i.split('\n'))
 
    country = list (country.split('\n'))
 
    print(country,'-', i)

import requests
 
ip = ['129.203.29.198', '148.187.4.164', '239.202.246.184', '245.184.161.17',
      '179.83.187.56', '101.159.154.180', '127.153.44.165',
      '31.6.213.69', '175.72.176.94', '131.113.160.111', '98.70.55.74']
res = {}
 
for i in ip:
    country = requests.get('http://freegeoip.net/json/' + i).json().get('country_name')
    country = country if country else 'other'
    res.setdefault(country, list()).append(i)
 
print(res)

some_value = 1
some_value2 = '1, 3, 45'
print('{}: {}'.format(some_value, some_value2))

import requests
input_file = None
with open ('ips.txt', 'r') as input_ip:
    input_file = input_ip.read().split('\n')
    ips = list(input_file)
report = {}
for i in  ips:
    country = requests.get('http://freegeoip.net/json/' + i).json().get('country_name')
    country = country if country else 'Unknown_country'
    report.setdefault(country, list()).append(i)
key_country = report.keys()
with open('output.txt','w') as out:
    for i in key_country:
        ip = (report[i])
        str_ip = ', '.join(ip)
        out.write('{}: {}''\n'.format(i, str_ip))
        out.write('\n')
print ('Done!')