def METHOD_NAME(self, num_convs, num_fcs, in_channels):
    last_layer_dim = in_channels
    # add branch specific conv layers
    convs = nn.ModuleList()
    if num_convs > 0:
        for i in range(num_convs):
            conv_in_channels = (
                last_layer_dim if i == 0 else self.conv_out_channels)
            convs.append(
                ConvModule(
                    conv_in_channels,
                    self.conv_out_channels,
                    3,
                    padding=1,
                    conv_cfg=self.conv_cfg,
                    norm_cfg=self.norm_cfg))
        last_layer_dim = self.conv_out_channels
    # add branch specific fc layers
    fcs = nn.ModuleList()
    if num_fcs > 0:
        last_layer_dim *= (self.roi_feat_size * self.roi_feat_size)
        for i in range(num_fcs):
            fc_in_channels = (
                last_layer_dim if i == 0 else self.fc_out_channels)
            fcs.append(nn.Linear(fc_in_channels, self.fc_out_channels))
        last_layer_dim = self.fc_out_channels
    return convs, fcs, last_layer_dim