#    Copyright 2020 Division of Medical Image Computing, German Cancer Research Center (DKFZ), Heidelberg, Germany
#
#    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 torch import nn


class Identity(nn.Module):
    def __init__(self, *args, **kwargs):
        super().__init__()

    def forward(self, input):
        return input


class MyGroupNorm(nn.GroupNorm):
    def __init__(self, num_channels, eps=1e-5, affine=True, num_groups=8):
        super(MyGroupNorm, self).__init__(num_groups, num_channels, eps, affine)