from itertools import groupby
from operator import itemgetter
from pprint import pprint
data = [{'Organization': '123 Solar', 'Phone': '444-444-4444', 'Email': '',
    'website': 'www.123solar.com'}, {'Organization': '123 Solar', 'Phone':
    '', 'Email': 'joey@123solar.com', 'Website': 'www.123solar.com'}, {
    'Organization': '234 test', 'Phone': '111', 'Email': 'a@123solar.com',
    'Website': 'b.123solar.com'}, {'Organization': '234 test', 'Phone':
    '222', 'Email': 'ac@123solar.com', 'Website': 'bd.123solar.com'}]
data = sorted(data, key=itemgetter('Organization'))
result = {}
for key, group in groupby(data, key=itemgetter('Organization')):
    result[key] = [item for item in group]
pprint(result)
Сортировать список словарей при объединении дубликатов в Python?