[Solved] What is wrong with this state schema?class ProfileState: age: int hobbies: list — Ans: The type hint for hobbies should specify the list item type, e.g., list[str]. | LangChain

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What is wrong with this state schema?

class ProfileState:
    age: int
    hobbies: list

AThe age field must be a string, not int.

BClass must inherit from a base schema class.

CThe type hint for hobbies should specify the list item type, e.g., list[str].

DThere should be no type hints in state schemas.

Step-by-Step Solution

Solution:

Step 1: Analyze the type hint for hobbies
Using just list is allowed but incomplete; specifying item type like list[str] improves clarity and validation.
Step 2: Check other options
Age as int is correct, inheritance is optional, and type hints are required for clarity.
Final Answer:
The type hint for hobbies should specify the list item type, e.g., list[str]. -> Option C
Quick Check:
Specify item types in collections for clarity [OK]

Quick Trick: Always specify item types in list type hints [OK]

Common Mistakes:

MISTAKES

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