Checking host availability with Python's Low-level networking interface and AWS Lambda

echolambda.py

from socket import socket, AF_INET, SOCK_STREAM

addresses = [
    {'example.com': 80},
    {'example.com': 443},
    {'host-1234567890-notexist.example.com': 1234}]

def echo(addresses: list):
    results = {}

    for address in addresses:
        for host, port in address.items():
            try:
                s = socket(AF_INET, SOCK_STREAM)
                s.connect((str(host), int(port)))
            except OSError:
                results[f'{host}:{port}'] = False
            else:
                s.close
                results[f'{host}:{port}'] = True

    return results

def lambda_handler(event, context):
    return echo(addresses)