EPAM Systems front-end components often transform arrays of configuration or display data before rendering. Implement a Python equivalent of JavaScript's Array.map() behavior.
Create array_map(items, operation) that returns a new array containing one transformed value for each input element. The operation represents the callback supplied to map and receives the current value, its zero-based index, and the original array. For JSON-compatible tests, represent the callback with one of these operation names: identity, double, square, or value_plus_index.
The function must preserve input order, include exactly one output for every input element, and leave the original array unchanged. Do not use Python's built-in map() or list comprehensions for the main implementation.
items, a list of integers, and operation, a supported string operation.identity returns the value unchanged.double returns value * 2.square returns value * value.value_plus_index returns value + index.def array_map(items, operation):