Step 1. Write a test: Write a test that tests for the new class or function that you want to add to your code. Think about the class name and structure you will need in order to call the new capability that doesn't exist yet - and nothing more.
Step 2. Test fails: Of course, the test fails because you haven't written the part that works yet.
The idea here is to think about the class or function you want and test for its intended output. This initial test failure shows you exactly where you should focus your code writing to get it to pass.
This is like starting with your end state in mind, which is the most effective way to accomplish a goal.
Step 3. Write some code: Write only the code needed to make the new function or class successfully pass. This is about efficiency and focus.
Step 4. Test passes: The test now passes, and the code works.
Step 5. Refactor: Clean up the code as necessary, removing any test stubs or hard-coded variables used in testing. Refine the code, if needed, for speed.

RESTCONF is a protocol used to access data defined in YANG using standard HTTP methods. However, it does not support distributed transactions, which is a requirement in this scenario.
* RESTCONF: Supports YANG data models, XML encoding, and can be used in environments with software redundancy.
* Distributed Transactions: RESTCONF does not support distributed transactions, which require coordination of a transaction across multiple network devices or components.
Option C is correct as the requirement for distributed transactions prevents the use of RESTCONF.
Reference:
Cisco DevNet Documentation: RESTCONF Protocol

An HTTP 502 Bad Gateway error indicates that the server acting as a gateway or proxy received an invalid response from the upstream server. This suggests there may be an issue with the configuration or availability of the server behind the load balancer.
* HTTP 502 Error: This error occurs when the load balancer or gateway receives an invalid response from the backend server.
* Server Configuration: The issue is likely due to misconfiguration or problems with the backend server that needs to be resolved.
Option A is correct as it identifies that the issue lies with the server configuration behind the load balancer.
Reference:
NGINX Documentation: Troubleshooting 502 Errors

Explanation:
Step 1: git add .
Step 2: git commit -m "this is my edit"
Step 3: git push <repository>
(if the remote repository is not connect yet, we will need to use a Step 2.5 of "git remote add origin <url>"

https://docs.python.org/3/library/unittest.html
assertTrue() or assertFalse() to verify a condition