Python Circuit Bandwidth API Integration

I have a partially-written Python script that needs to talk to an external API so I can both increase and decrease the bandwidth of existing circuits on demand. The core logic—authentication, endpoint calls, parameter handling, and response parsing—still needs cleaning up, and I want to wrap it in a small, reusable module (plus a quick demo script) that I can drop into other tools later.

Here is what I need from you:

• Review the code I already have, identify any bugs or gaps, and refactor it for clarity and reliability.
• Implement the missing calls that raise or lower the bandwidth, with proper error handling and logging.
• Expose the key operations through simple functions such as increase_bandwidth(circuit_id, new_rate) and decrease_bandwidth(circuit_id, new_rate).
• Add a short CLI or Jupyter example that shows the functions in action against the sandbox environment (or mocked responses if you do not have live access).
• Provide concise setup notes so I can recreate your environment and extend the script on my side.

Acceptance criteria: the script executes without unhandled exceptions, reports success/failure clearly, and I can run a test that changes a circuit from X to Y Mbps and back again in the sandbox.

I predominantly work with Python 3.11 and the standard requests library, but I am open to using httpx or asyncio if you believe it adds value.