find_nested_val

## for finding the keys and/or indices on the path to a target variable in a nested data structure ###
## example usage at https://stackoverflow.com/a/76448138/6146136                            ##########


def yield_key_paths(objC, valT, kPath=None, validTypes=(tuple,list,dict,set)):
    ''' Traverse objC data structure recursively to yield path/s to valT'''
    if not isinstance(kPath, list): kPath = []
    if objC == valT: yield kPath

    if not isinstance(objC, validTypes): return
    for k,v in (objC.items() if isinstance(objC,dict) else enumerate(objC)):
        yield from yield_key_paths(v, valT, kPath+[k], validTypes)


def find_nested_val(obj, val, findAll=False, validTypes=(tuple,list,dict,set)):
    '''Get a list of or the first path to val in obj (No path -> [] or None)'''
    paths = yield_key_paths(obj, val, [], validTypes)
    return list(paths) if findAll else next(paths, None)