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""" Provides support utilities for flattening."""
from typing import List, Tuple, Union
[docs]def flatten(nested_list: Union[List, Tuple]) -> List:
"""Flatten an arbitrarily nested iterable.
Args:
nested_list:
An arbitrarily nested iterable to be flattened.
Returns:
A list containing a flattened version of the arbitrarily nested input.
"""
flat_list = []
if not isinstance(nested_list, (list, tuple)):
raise ValueError(
f"Expected object of type list or tuple, not {type(nested_list)}"
)
for item in nested_list:
if isinstance(item, (list, tuple)):
flat_list.extend(flatten(item))
else:
flat_list.append(item)
return flat_list