test.py

import json
import requests
import sys

base_req = "https://atlas.ripe.net/api/v2/measurements/?is_public=true&fields=id&page_size=20000&format=json&type=ping"

outfile = open("output.json", "w")

next_url = base_req
while next_url is not None:
	print "Fetching ",next_url
	r = requests.get(next_url)
	if r.status_code != 200:
		sys.exit(1)
	j = r.json()

	outfile.write(json.dumps(j["results"], indent=2))

	next_url = j["next"]

	if next_url is None and len(j["results"]) > 0:
		next_url = base_req + "&id__gt=" + str(j["results"][-1]["id"])

outfile.close()