import json

owner_id = ['owner1', 'owner2', 'owner3', 'owner2'] # дважды owner2 сделано специально
media_id = ['media1', 'media2', 'media3', 'media4']

result = {}
result['result'] = []

for owner, media in zip(owner_id, media_id):
    result['result'].append({owner: media})


print(result)
# output: 
# {'result': [{'owner1': 'media1'}, {'owner2': 'media2'}, {'owner3': 'media3'}, {'owner2': 'media4'}]}