How many unique AWS EC2 IPv4 Addresses are there?

aws_ec2_unique_ipv4.py

import ipaddress
import json
from collections import defaultdict
from itertools import chain
from urllib.request import urlopen

with urlopen("https://ip-ranges.amazonaws.com/ip-ranges.json") as req:
    resp_json = json.loads(req.read())
ip_prefixes_and_regions = (
    (x["ip_prefix"], x["region"])
    for x in resp_json["prefixes"]
    if x["service"].upper() == "EC2"
)

region_to_ip_ranges_map = defaultdict(list)
for ip_prefix, region in ip_prefixes_and_regions:
    region_to_ip_ranges_map[region].append(ip_prefix)

regions, ip_ranges = zip(*region_to_ip_ranges_map.items())

all_ip_ranges = chain.from_iterable(ip_ranges)

nets = (ipaddress.ip_network(_ip) for _ip in all_ip_ranges)
cidrs = (
    str(ip_range).strip() for ip_range in ipaddress.collapse_addresses(nets)  # type:ignore
)

# ips = []
ip_count = 0
for cidr in cidrs:
    for ip_address in ipaddress.IPv4Network(cidr):
        # ips.append(ip_address)
        ip_count += 1

print("Number of unique Amazon EC2 IPv4 addresses:", "{:,}".format(ip_count))