import json, requests, sys

endpoint = "https://api.millercenter.org/speeches"
out_file = "speeches.json"

r = requests.post(url=endpoint)
data = r.json()
items = data['Items']

while 'LastEvaluatedKey' in data:
    parameters = {"LastEvaluatedKey": data['LastEvaluatedKey']['doc_name']}
    r = requests.post(url = endpoint, params = parameters)
    data = r.json()
    items += data['Items']
    print(f'{len(items)} speeches')

with open(out_file, "w") as out:
    out.write(json.dumps(items))
    print(f'wrote results to file: {out_file}')