read_line_by_line_yield.py

import json

def csv_reader(file_name):
    for row in open(file_name, "r"):
        yield row

total = 0
for line in csv_reader("full.sjson"):
    content = json.loads(line)
    if 'housenumbers' in content:
        total += len(content['housenumbers'].keys())
    else:
        total += 1

print(total)