Lesson 17. Look up a record by two keys

Why this matters

An author name alone may identify several library books. Our catalog also needs two keys: activity and information type. Lesson 15 already extracted this pair from a short question.

Before running

Copy facts.json from step 16 into the new folder. This program asks for the two keys separately so we can test lookup first. and requires both comparisons to be true. matches stores matching cards.

[
  {"club": "шахмат", "kind": "уақыт", "value": "бейсенбі, 15:00"},
  {"club": "шахмат", "kind": "орын", "value": "203-бөлме"}
]

From the project root, enter the step folder and run the program:

cd course/kazakh-ai/step-17
python3 search.py

On Windows, use py search.py instead of the last command.

import json

with open("facts.json", encoding="utf-8") as file:
    facts = json.load(file)
club = input("Үйірме: ").lower()
kind = input("Мәлімет түрі: ").lower()
matches = []
for fact in facts:
    if fact["club"] == club and fact["kind"] == kind:
        matches.append(fact)
if len(matches) == 1:
    print("Табылды:", matches[0]["value"])
elif len(matches) == 0:
    print("білмеймін: дерек жоқ")
else:
    print("тоқта: бірнеше дерек табылды")

Step files.

How the program works

The loop visits every card. A card enters matches only when both fields match. With exactly one match, [0] is safe; with none, we say no record exists; with several, we stop because we cannot choose yet. .lower() handles capitals but does not fix spelling or extra spaces.

Support map

Activity + type → scan catalog → 0: missing; 1: value; 2 or more: stop.

Recall and check

Predict the output for шахмат + уақыт, then сурет + орын. Hint: both fields must match. Expected: Табылды: бейсенбі, 15:00; then білмеймін: дерек жоқ. Add a second chess time card and verify the stop. Common mistake: accepting the first match before scanning the whole catalog.