[Solved] Find the error in this transition check:def can_transition(current, next_state): valid = { 'Pending': ['Processing', 'Cancelled'], 'Processing': ['Shipped'] } return next_state in valid[current] | LLD

LLD - Design — Online Shopping Cart

Find the error in this transition check:

def can_transition(current, next_state):
    valid = {
        'Pending': ['Processing', 'Cancelled'],
        'Processing': ['Shipped']
    }
    return next_state in valid[current]

AReturns True for invalid transitions

BNo error, function works correctly

CKeyError if current state not in valid dictionary

DSyntax error due to missing colon

Step-by-Step Solution

Solution:

Step 1: Check dictionary access
Function accesses valid[current] without checking if current exists.
Step 2: Identify potential error
If current state is unknown, KeyError occurs.
Final Answer:
KeyError if current state not in valid dictionary -> Option C
Quick Check:
Missing key check causes KeyError [OK]

Quick Trick: Always check dictionary keys before access [OK]

Common Mistakes:

MISTAKES

Assuming all states exist in dictionary
Ignoring KeyError possibility
Confusing syntax errors with runtime errors

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Find the error in this transition check:

Step 1: Check dictionary access

Step 2: Identify potential error

Final Answer:

Quick Check:

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