Extend an Existing Python Class | Dataford Interview Questions

Given existing Python code with a couple of classes and functions, write another class implementing a new function that extends it.

Asked in the coding stage. Assume the existing RecordProcessor.transform(record) method returns record["amount"]. Implement aggregate_records(records), which uses a subclass and returns a dictionary mapping each category to the sum of transformed amounts.

Input and Output

records is a list of dictionaries, each containing a string category and integer amount. Return a dictionary whose keys are categories and whose values are integer totals. Return {} for an empty list.

Constraints

0 <= len(records) <= 10^4
Each record contains a string category field
Each record contains an integer amount field
Category names may repeat
Amounts may be negative

Function Signature

def aggregate_records(records):

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