Any short cut to add '>>>' in from of lines in the docstring?

After we copy several lines of code to the docstring for doc test, is there a shortcut to automatically add '>>>' in front of the code?

For example, in the following docstring, the doctest code is long, it is really tedious to add '>>>' for every line.

def iter_leaves_with_another(tree: Mapping, iter_with: Mapping, default: Callable = dict):
    """
    Iterates through the leaves of the tree (represented by nested mappings), together with another mapping.
    This method can be applied to construct a dictionary with the same structure as the `tree`, with some transformations on the values.

    For example,
    >>> import utilx.dict_ext as dx
    >>> reconstruct = {}
    >>> for d, k, v in dx.iter_leaves_with_another({
    >>>     'a': 1,
    >>>     'b': {'b1': 2,
    >>>           'b2': {'b21': 3,
    >>>                  'b22': 4,
    >>>                  'b23': {'b231': 5}}},
    >>>     'c': 6,
    >>>     'd': {'d1': 7,
    >>>           'd2': 8,
    >>>           'd3': {},
    >>>           'd4': {'d41': 9,
    >>>                  'd42': 10}}
    >>> }, iter_with=reconstruct, default=dict):
    >>>     d[k] = v + 1
    >>>
    >>> # the following prints out the same tree structure, with all values being added by 1.
    >>> # i.e. {'a': 2, 'b': {'b1': 3, 'b2': {'b21': 4, 'b22': 5, 'b23': {'b231': 6}}}, 'c': 7, 'd': {'d1': 8, 'd2': 9, 'd3': {}, 'd4': {'d41': 10, 'd42': 11}}}
    >>> print(reconstruct)

    :param tree: represented by a nested mapping.
    :param iter_with: iterate through the leaves of the `tree` together with this mapping.
    :param default: a callable that returns an object assigned to a key when it is not found in the `iter_with`.
    :return: an iterator; yields a three-tuple at a time: 1) a sub-mapping in `iter_with` that corresponds to the current level in the `tree` being iterated through; 2) the key; 3) the value.
    """
    for k, v in tree.items():
        if isinstance(v, Mapping):
            if k not in iter_with:
                iter_with[k] = default()
            yield from iter_leaves_with_another(tree=v, iter_with=iter_with[k], default=default)
        else:
            yield iter_with, k, v