Python function get dictionary's value from nested with dot annotation key

get_nested_value.py

from functools import reduce

def get_nested_value(nested_dict, str_key):
  """
  Get value from nested-dict via dot-annotation key
  Parameters:
    nested_dict: dict
    str_key: str
    
  Example:
  nested = {"a": {"aa": "aaa"}}
  key = "a.aa"
  aa = get_nested_value(nested, key)
  """
  return reduce(lambda data, key: data.get(key), str_key.split('.'), nested_dict)