The article describes how to build a simple call center using Twilio Programmable Voice and Python. The call center allows customers to wait in a conference with other waiting customers until an agent is available to connect them. If the customer hangs up, they are removed from the queue. The system uses Flask as the microframework and handles incoming calls by adding the caller's phone number and CallSid to two queues: CUSTOMER_QUEUE and AGENT_QUEUE. When an agent calls in, their phone number is added to the AGENT_QUEUE, and if there is a customer available, they are connected immediately. Otherwise, they wait in a conference with other customers until one hangs up or an agent is available. The system also includes a CustomerRedirect Thread that handles redirecting customers to agents after the agent has been connected. The call center can be tested by navigating to the ngrok URL and calling the Twilio number.