import copy


def _get_value(item, key):
    """Grabs a nested value within a dict

    :param dict item: the dictionary
    :param str key: the nested key to find
    :returns: the value if found, otherwise None
    """
    keys = key.split('.', 1)

    if isinstance(item, dict):
        if len(keys) == 2:
            if keys[0] in item:
                return _get_value(item[keys[0]], keys[1])
        elif keys[0] in item:
            return copy.deepcopy(item[keys[0]])