<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def iterate_dict(container, exclude=None, path=None):
 """Iterate over a nested dictionary. The dictionary is iterated over in a depth first manner. :param container: Dictionary to iterate over :param exclude: Optional callable, which is given key and value as arguments and may return True to stop iteration of that branch :return: (path, key, value) tuple """

    if path is None:
        path = []

    for key, value in container.items():
        if callable(exclude) and exclude(key, value):
            continue

        if isinstance(value, collections.Mapping):
            for inner_path, inner_key, inner_value in iterate_dict(value, exclude=exclude, path=path + [key]):
                yield inner_path, inner_key, inner_value

        yield path, key, value