Return the value of a data_structure given a path.

    :param data_structure: Dictionary, list or subscriptable object.
    :param key: Array with the defined path ordered.

def _get_value(data_structure, key):
    """Return the value of a data_structure given a path.

    :param data_structure: Dictionary, list or subscriptable object.
    :param key: Array with the defined path ordered.
    """
    if len(key) == 0:
        raise KeyError()
    value = data_structure[key[0]]
    if len(key) > 1:
        return _get_value(value, key[1:])
    return value