# Copyright 2020 BMW Group
#
# Licensed under the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License. You may obtain
# a copy of the License at
#
#      http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.

from collections import defaultdict


class DefaultKeyDict(defaultdict):
    """A defaultdict with the key passed to the default factory."""

    def __init__(self, default_factory):
        self.factory = default_factory

    def __missing__(self, key):
        item = self[key] = self.factory(key)
        return item