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Cleaning Data in Python
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Cleaning Data in Python

MediumPython

Problem

Implement a function to transform and clean a dataset in Python.

Write clean_dataset(records) for a list of dictionaries containing id, name, email, and age. Trim string fields, lowercase emails, convert valid numeric age strings to integers, discard records with missing or invalid required values, and keep only the first valid record for each normalized ID. Return a new list containing dictionaries with the keys id, name, email, and age.

Constraints

  • 0 <= len(records) <= 10000
  • Each record is a dictionary
  • Required keys are id, name, email, and age
  • ID, name, and email must be strings before normalization
  • Age must be an integer or a string containing decimal digits
  • Valid ages are between 0 and 120 inclusive
  • The first valid record for each normalized ID is retained

Function Signature

def clean_dataset(records):
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