src/transformers/models/swin2sr/modeling_swin2sr.py/PixelShuffleUpsampler/__init__
class PixelShuffleUpsampler:    def __init__(self, config, num_features):
        super().__init__()
        self.conv_before_upsample = nn.Conv2d(config.embed_dim, num_features, 3, 1, 1)
        self.activation = nn.LeakyReLU(inplace=True)
        self.upsample = Upsample(config.upscale, num_features)
        self.final_convolution = nn.Conv2d(num_features, config.num_channels, 3, 1, 1)