import torch.nn as nn
class BatchNorm(nn.BatchNorm2d):
    def __init__(self, num_features, eps=1e-05, momentum=0.1, weight=True, bias=True):
        super().__init__(num_features, eps=eps, momentum=momentum)
        self.weight.data.fill_(1.0)
        self.bias.data.fill_(0.0)
        self.weight.requires_grad = weight
        self.bias.requires_grad = bias