Python Tracebacks
The Bottom Line Is Usually At The Bottom
Python errors often print several lines called a traceback. Read from the bottom upward:
This tells you the immediate problem: Python cannot find the file at the path you gave it.
Common Week 5 Errors
| Error | Likely cause | First fix |
|---|---|---|
FileNotFoundError |
path is wrong, file is in another folder, or capitalization differs | check the relative path from the notebook location |
ModuleNotFoundError |
package is missing | add the package to requirements.txt and install it in the Codespace |
KeyError |
column name is misspelled or not present | run nhanes.columns.tolist() |
IndentationError |
Python block spacing is inconsistent | re-indent the block with four spaces |
NameError |
object has not been created in the current kernel | rerun earlier cells in order |
AI Debugging Prompt
Read this Python traceback from the bottom up. Identify the error type, the exact object or path causing the issue, and the smallest code change that would fix it. Do not rewrite the full analysis.
Student Check
When you fix an error, add one sentence to your notebook explaining what failed and how you knew the fix worked.