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Flatten Complex JSON
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Flatten Complex JSON

MediumPython

Problem

Write a Python function to parse a complex JSON file and flatten it into a table.

Implement flatten_json(json_text). The input is a JSON string containing an array of objects. Flatten nested object keys using dot notation, such as customer.address.city. Arrays of objects must expand into multiple rows, while arrays of scalar values remain unchanged in their flattened field. Return a list of dictionaries. Missing fields may be absent from individual output rows. Arrays are either arrays of objects or arrays of scalar values.

Constraints

  • The input is valid JSON text.
  • The top-level JSON value is an array of objects.
  • Nested object keys are unique within their path.
  • Arrays contain either only objects or only scalar values.
  • The returned value is a list of dictionaries.
  • Nested object arrays may create multiple output rows per input record.

Function Signature

def flatten_json(json_text):
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