The answer is that the build is failing because the source code does not contain a setup.py file in the root directory. The buildspec.yml’s build phase runs the command `python setup.py sdist`, which explicitly expects this file at the project root to package the application, but if setup.py is missing or located inside a subdirectory like src/, Python will throw a FileNotFoundError. On the AWS Certified DevOps Engineer Professional DOP-C02 exam, this question tests your ability to trace build failures to mismatches between the buildspec commands and the actual repository structure—a common trap is assuming the error stems from unsupported runtimes or test phases, when in reality the pre_build flake8 check on src/ works fine while the build command fails. Remember the memory tip: “Root the build command” — always verify that any file referenced in the build phase (like setup.py or package.json) exists exactly where the command expects it, not in a subdirectory.
DOP-C02 SDLC Automation Practice Question
This DOP-C02 practice question tests your understanding of sdlc automation. The scenario asks you to isolate a root cause — eliminate options that address a different problem before choosing. After answering, compare your reasoning against the explanation and wrong-answer breakdown below. Once you have made your selection, read the full explanation to reinforce the concept and understand why each distractor is designed to mislead on exam day.
Refer to the exhibit. The above buildspec.yml is used in AWS CodeBuild. The build is failing during the 'build' phase with a 'FileNotFoundError: setup.py' error. What is the MOST likely cause?
Clue words in this question
Noticing these words before you look at the options changes how you read each choice.
Clue: "most likely"
Why it matters: Probability qualifier — the question wants the most probable cause or outcome, not a guaranteed one. Eliminate low-probability options.
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
The source code does not contain a setup.py file in the root directory.
Option B is correct because the pre_build phase runs flake8 on src/ directory, but the build command expects setup.py in the root; setup.py might be in src/ or missing. Option A is wrong because Python 3.8 is supported. Option C is wrong because unit tests are in post_build, not causing build failure. Option D is wrong because artifacts are only collected after build.
Key principle: NAT direction and interface roles matter as much as the IP address mapping. Inside/outside designation controls which traffic is translated.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
✓
The source code does not contain a setup.py file in the root directory.
Why this is correct
The build command runs python setup.py build, which requires setup.py in the current directory.
Clue confirmation
The clue word "most likely" in the question point toward this answer.
Related concept
Static NAT maps one inside address to one outside address.
✗
The unit tests in the post_build phase are failing.
Why it's wrong here
Tests run after build, so they do not cause build phase failure.
✗
The Python version 3.8 is not supported by CodeBuild.
Why it's wrong here
CodeBuild supports Python 3.8.
✗
The artifacts configuration discarding paths is causing the error.
Why it's wrong here
Artifacts configuration does not affect build execution.
Common exam traps
Common exam trap: NAT rules depend on direction and matching traffic
NAT is not only about the public address. The inside/outside interface roles and the ACL or rule that matches traffic are just as important.
Detailed technical explanation
How to think about this question
NAT questions usually test address translation, overload/PAT behaviour, static mappings and whether the right traffic is being translated. Read the interface direction and address terms carefully.
KKey Concepts to Remember
Static NAT maps one inside address to one outside address.
PAT allows many inside hosts to share one public address using ports.
Inside local and inside global describe the private and translated addresses.
NAT ACLs identify traffic for translation, not always security filtering.
TExam Day Tips
→Identify inside and outside interfaces first.
→Check whether the scenario needs static NAT, dynamic NAT or PAT.
→Do not confuse NAT matching ACLs with normal packet-filtering intent.
Key takeaway
NAT direction and interface roles matter as much as the IP address mapping. Inside/outside designation controls which traffic is translated.
Real-world example
How this comes up in practice
A cloud solutions architect for a retail company is evaluating services for a new workload. The correct answer here reflects best practice for the specific scenario described — not a general cloud recommendation. NAT direction and interface roles matter as much as the IP address mapping. Inside/outside designation controls which traffic is translated. Cloud exam questions reward reading the constraint carefully: the same technology can be right or wrong depending on the use case.
What to study next
Got this wrong? Here's your next step.
Review the four NAT address types (inside local, inside global, outside local, outside global), PAT port overload, and static vs dynamic NAT use cases. Then practise related DOP-C02 NAT questions on configuration and troubleshooting.
SDLC Automation — This question tests SDLC Automation — Static NAT maps one inside address to one outside address..
What is the correct answer to this question?
The correct answer is: The source code does not contain a setup.py file in the root directory. — Option B is correct because the pre_build phase runs flake8 on src/ directory, but the build command expects setup.py in the root; setup.py might be in src/ or missing. Option A is wrong because Python 3.8 is supported. Option C is wrong because unit tests are in post_build, not causing build failure. Option D is wrong because artifacts are only collected after build.
What should I do if I get this DOP-C02 question wrong?
Review the four NAT address types (inside local, inside global, outside local, outside global), PAT port overload, and static vs dynamic NAT use cases. Then practise related DOP-C02 NAT questions on configuration and troubleshooting.
Are there clue words in this question I should notice?
Yes — watch for: "most likely". Probability qualifier — the question wants the most probable cause or outcome, not a guaranteed one. Eliminate low-probability options.
What is the key concept behind this question?
Static NAT maps one inside address to one outside address.
About these practice questions
Courseiva creates original exam-style practice questions with explanations and wrong-answer analysis. It does not publish real exam questions, exam dumps, or protected exam content. Learn why practice questions differ from exam dumps →
Share a tip, memory trick, or ask about the reasoning behind this question. Do not post real exam questions, leaked content, braindumps, or copyrighted exam material. Comments are moderated and may be removed without notice.
This DOP-C02 practice question is part of Courseiva's free Amazon Web Services certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the DOP-C02 exam.
Question Discussion
Share a tip, memory trick, or ask about the reasoning behind this question. Do not post real exam questions, leaked content, braindumps, or copyrighted exam material. Comments are moderated and may be removed without notice.
Sign in to join the discussion.