Constructor to create pytorch model.
pip install model-constructor
Or install from repo:
pip install git+https://github.com/ayasyrev/model_constructor.git
First import constructor class, then create model constructor object.
Now you can change every part of model.
from model_constructor import ModelConstructormc = ModelConstructor()Check base parameters:
mcoutput
ModelConstructor in_chans: 3, num_classes: 1000 expansion: 1, groups: 1, dw: False, div_groups: None act_fn: ReLU, sa: False, se: False stem sizes: [64], stride on 0 body sizes [64, 128, 256, 512] layers: [2, 2, 2, 2]
Check all parameters with print_cfg method:
mc.print_cfg()output
ModelConstructor( in_chans=3 num_classes=1000 block='BasicBlock' conv_layer='ConvBnAct' block_sizes=[64, 128, 256, 512] layers=[2, 2, 2, 2] norm='BatchNorm2d' act_fn='ReLU' expansion=1 groups=1 bn_1st=True zero_bn=True stem_sizes=[64] stem_pool="MaxPool2d {'kernel_size': 3, 'stride': 2, 'padding': 1}" init_cnn='init_cnn' make_stem='make_stem' make_layer='make_layer' make_body='make_body' make_head='make_head')  Now we have model constructor, default setting as resnet18. And we can get model after call it.
model = mc() modeloutput
ModelConstructor( (stem): Sequential( (conv_1): ConvBnAct( (conv): Conv2d(3, 64, kernel_size=(7, 7), stride=(2, 2), padding=(3, 3), bias=False) (bn): BatchNorm2d(64, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) (act_fn): ReLU(inplace=True) ) (stem_pool): MaxPool2d(kernel_size=3, stride=2, padding=1, dilation=1, ceil_mode=False) ) (body): Sequential( (l_0): Sequential( (bl_0): BasicBlock( (convs): Sequential( (conv_0): ConvBnAct( (conv): Conv2d(64, 64, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(64, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) (act_fn): ReLU(inplace=True) ) (conv_1): ConvBnAct( (conv): Conv2d(64, 64, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(64, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) ) ) (act_fn): ReLU(inplace=True) ) (bl_1): BasicBlock( (convs): Sequential( (conv_0): ConvBnAct( (conv): Conv2d(64, 64, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(64, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) (act_fn): ReLU(inplace=True) ) (conv_1): ConvBnAct( (conv): Conv2d(64, 64, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(64, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) ) ) (act_fn): ReLU(inplace=True) ) ) (l_1): Sequential( (bl_0): BasicBlock( (convs): Sequential( (conv_0): ConvBnAct( (conv): Conv2d(64, 128, kernel_size=(3, 3), stride=(2, 2), padding=(1, 1), bias=False) (bn): BatchNorm2d(128, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) (act_fn): ReLU(inplace=True) ) (conv_1): ConvBnAct( (conv): Conv2d(128, 128, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(128, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) ) ) (id_conv): Sequential( (id_conv): ConvBnAct( (conv): Conv2d(64, 128, kernel_size=(1, 1), stride=(2, 2), bias=False) (bn): BatchNorm2d(128, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) ) ) (act_fn): ReLU(inplace=True) ) (bl_1): BasicBlock( (convs): Sequential( (conv_0): ConvBnAct( (conv): Conv2d(128, 128, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(128, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) (act_fn): ReLU(inplace=True) ) (conv_1): ConvBnAct( (conv): Conv2d(128, 128, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(128, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) ) ) (act_fn): ReLU(inplace=True) ) ) (l_2): Sequential( (bl_0): BasicBlock( (convs): Sequential( (conv_0): ConvBnAct( (conv): Conv2d(128, 256, kernel_size=(3, 3), stride=(2, 2), padding=(1, 1), bias=False) (bn): BatchNorm2d(256, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) (act_fn): ReLU(inplace=True) ) (conv_1): ConvBnAct( (conv): Conv2d(256, 256, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(256, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) ) ) (id_conv): Sequential( (id_conv): ConvBnAct( (conv): Conv2d(128, 256, kernel_size=(1, 1), stride=(2, 2), bias=False) (bn): BatchNorm2d(256, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) ) ) (act_fn): ReLU(inplace=True) ) (bl_1): BasicBlock( (convs): Sequential( (conv_0): ConvBnAct( (conv): Conv2d(256, 256, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(256, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) (act_fn): ReLU(inplace=True) ) (conv_1): ConvBnAct( (conv): Conv2d(256, 256, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(256, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) ) ) (act_fn): ReLU(inplace=True) ) ) (l_3): Sequential( (bl_0): BasicBlock( (convs): Sequential( (conv_0): ConvBnAct( (conv): Conv2d(256, 512, kernel_size=(3, 3), stride=(2, 2), padding=(1, 1), bias=False) (bn): BatchNorm2d(512, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) (act_fn): ReLU(inplace=True) ) (conv_1): ConvBnAct( (conv): Conv2d(512, 512, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(512, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) ) ) (id_conv): Sequential( (id_conv): ConvBnAct( (conv): Conv2d(256, 512, kernel_size=(1, 1), stride=(2, 2), bias=False) (bn): BatchNorm2d(512, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) ) ) (act_fn): ReLU(inplace=True) ) (bl_1): BasicBlock( (convs): Sequential( (conv_0): ConvBnAct( (conv): Conv2d(512, 512, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(512, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) (act_fn): ReLU(inplace=True) ) (conv_1): ConvBnAct( (conv): Conv2d(512, 512, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(512, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) ) ) (act_fn): ReLU(inplace=True) ) ) ) (head): Sequential( (pool): AdaptiveAvgPool2d(output_size=1) (flat): Flatten(start_dim=1, end_dim=-1) (fc): Linear(in_features=512, out_features=1000, bias=True) ) )
If you want to change model, just change constructor parameters.
 Lets create resnet50.
mc.expansion = 4 mc.layers = [3,4,6,3]We can check, what we changed (compare to default constructor).
mc.changed_fieldsoutput
{'layers': [3, 4, 6, 3], 'expansion': 4} mc.print_changed_fields()output
Changed fields: layers: [3, 4, 6, 3] expansion: 4
We can compare changed with defaults.
mc.print_changed_fields(show_default=True)output
Changed fields: layers: [3, 4, 6, 3] | [2, 2, 2, 2] expansion: 4 | 1
Now we can look at model parts - stem, body, head.
mc.bodyoutput
Sequential( (l_0): Sequential( (bl_0): BasicBlock( (convs): Sequential( (conv_0): ConvBnAct( (conv): Conv2d(64, 64, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(64, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) (act_fn): ReLU(inplace=True) ) (conv_1): ConvBnAct( (conv): Conv2d(64, 64, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(64, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) ) ) (act_fn): ReLU(inplace=True) ) (bl_1): BasicBlock( (convs): Sequential( (conv_0): ConvBnAct( (conv): Conv2d(64, 64, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(64, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) (act_fn): ReLU(inplace=True) ) (conv_1): ConvBnAct( (conv): Conv2d(64, 64, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(64, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) ) ) (act_fn): ReLU(inplace=True) ) (bl_2): BasicBlock( (convs): Sequential( (conv_0): ConvBnAct( (conv): Conv2d(64, 64, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(64, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) (act_fn): ReLU(inplace=True) ) (conv_1): ConvBnAct( (conv): Conv2d(64, 64, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(64, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) ) ) (act_fn): ReLU(inplace=True) ) ) (l_1): Sequential( (bl_0): BasicBlock( (convs): Sequential( (conv_0): ConvBnAct( (conv): Conv2d(64, 128, kernel_size=(3, 3), stride=(2, 2), padding=(1, 1), bias=False) (bn): BatchNorm2d(128, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) (act_fn): ReLU(inplace=True) ) (conv_1): ConvBnAct( (conv): Conv2d(128, 128, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(128, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) ) ) (id_conv): Sequential( (id_conv): ConvBnAct( (conv): Conv2d(64, 128, kernel_size=(1, 1), stride=(2, 2), bias=False) (bn): BatchNorm2d(128, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) ) ) (act_fn): ReLU(inplace=True) ) (bl_1): BasicBlock( (convs): Sequential( (conv_0): ConvBnAct( (conv): Conv2d(128, 128, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(128, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) (act_fn): ReLU(inplace=True) ) (conv_1): ConvBnAct( (conv): Conv2d(128, 128, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(128, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) ) ) (act_fn): ReLU(inplace=True) ) (bl_2): BasicBlock( (convs): Sequential( (conv_0): ConvBnAct( (conv): Conv2d(128, 128, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(128, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) (act_fn): ReLU(inplace=True) ) (conv_1): ConvBnAct( (conv): Conv2d(128, 128, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(128, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) ) ) (act_fn): ReLU(inplace=True) ) (bl_3): BasicBlock( (convs): Sequential( (conv_0): ConvBnAct( (conv): Conv2d(128, 128, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(128, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) (act_fn): ReLU(inplace=True) ) (conv_1): ConvBnAct( (conv): Conv2d(128, 128, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(128, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) ) ) (act_fn): ReLU(inplace=True) ) ) (l_2): Sequential( (bl_0): BasicBlock( (convs): Sequential( (conv_0): ConvBnAct( (conv): Conv2d(128, 256, kernel_size=(3, 3), stride=(2, 2), padding=(1, 1), bias=False) (bn): BatchNorm2d(256, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) (act_fn): ReLU(inplace=True) ) (conv_1): ConvBnAct( (conv): Conv2d(256, 256, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(256, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) ) ) (id_conv): Sequential( (id_conv): ConvBnAct( (conv): Conv2d(128, 256, kernel_size=(1, 1), stride=(2, 2), bias=False) (bn): BatchNorm2d(256, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) ) ) (act_fn): ReLU(inplace=True) ) (bl_1): BasicBlock( (convs): Sequential( (conv_0): ConvBnAct( (conv): Conv2d(256, 256, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(256, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) (act_fn): ReLU(inplace=True) ) (conv_1): ConvBnAct( (conv): Conv2d(256, 256, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(256, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) ) ) (act_fn): ReLU(inplace=True) ) (bl_2): BasicBlock( (convs): Sequential( (conv_0): ConvBnAct( (conv): Conv2d(256, 256, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(256, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) (act_fn): ReLU(inplace=True) ) (conv_1): ConvBnAct( (conv): Conv2d(256, 256, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(256, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) ) ) (act_fn): ReLU(inplace=True) ) (bl_3): BasicBlock( (convs): Sequential( (conv_0): ConvBnAct( (conv): Conv2d(256, 256, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(256, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) (act_fn): ReLU(inplace=True) ) (conv_1): ConvBnAct( (conv): Conv2d(256, 256, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(256, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) ) ) (act_fn): ReLU(inplace=True) ) (bl_4): BasicBlock( (convs): Sequential( (conv_0): ConvBnAct( (conv): Conv2d(256, 256, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(256, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) (act_fn): ReLU(inplace=True) ) (conv_1): ConvBnAct( (conv): Conv2d(256, 256, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(256, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) ) ) (act_fn): ReLU(inplace=True) ) (bl_5): BasicBlock( (convs): Sequential( (conv_0): ConvBnAct( (conv): Conv2d(256, 256, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(256, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) (act_fn): ReLU(inplace=True) ) (conv_1): ConvBnAct( (conv): Conv2d(256, 256, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(256, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) ) ) (act_fn): ReLU(inplace=True) ) ) (l_3): Sequential( (bl_0): BasicBlock( (convs): Sequential( (conv_0): ConvBnAct( (conv): Conv2d(256, 512, kernel_size=(3, 3), stride=(2, 2), padding=(1, 1), bias=False) (bn): BatchNorm2d(512, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) (act_fn): ReLU(inplace=True) ) (conv_1): ConvBnAct( (conv): Conv2d(512, 512, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(512, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) ) ) (id_conv): Sequential( (id_conv): ConvBnAct( (conv): Conv2d(256, 512, kernel_size=(1, 1), stride=(2, 2), bias=False) (bn): BatchNorm2d(512, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) ) ) (act_fn): ReLU(inplace=True) ) (bl_1): BasicBlock( (convs): Sequential( (conv_0): ConvBnAct( (conv): Conv2d(512, 512, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(512, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) (act_fn): ReLU(inplace=True) ) (conv_1): ConvBnAct( (conv): Conv2d(512, 512, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(512, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) ) ) (act_fn): ReLU(inplace=True) ) (bl_2): BasicBlock( (convs): Sequential( (conv_0): ConvBnAct( (conv): Conv2d(512, 512, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(512, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) (act_fn): ReLU(inplace=True) ) (conv_1): ConvBnAct( (conv): Conv2d(512, 512, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(512, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) ) ) (act_fn): ReLU(inplace=True) ) ) )
Alternative we can create config first and than create constructor from it.
from model_constructor import ModelCfgcfg = ModelCfg( num_classes=10, act_fn=nn.Mish, ) print(cfg)output
ModelCfg( in_chans=3 num_classes=10 block='BasicBlock' conv_layer='ConvBnAct' block_sizes=[64, 128, 256, 512] layers=[2, 2, 2, 2] norm='BatchNorm2d' act_fn='Mish' expansion=1 groups=1 bn_1st=True zero_bn=True stem_sizes=[64] stem_pool="MaxPool2d {'kernel_size': 3, 'stride': 2, 'padding': 1}")  When creating config or constructor we can use string annotation for nn.Modules - it useful when creating model from config files.
cfg = ModelCfg( num_classes=10, act_fn="nn.SELU", ) print(cfg.act_fn)output
class 'torch.nn.modules.activation.SELU'
Now we can create constructor from config:
mc = ModelConstructor.from_cfg(cfg) mcoutput
ModelConstructor in_chans: 3, num_classes: 10 expansion: 1, groups: 1, dw: False, div_groups: None act_fn: SELU, sa: , se: SEModule stem sizes: [64], stride on 0 body sizes [64, 128, 256, 512] layers: [2, 2, 2, 2]
Main purpose of this module - fast and easy modify model. And here is the link to more modification to beat Imagenette leaderboard with add MaxBlurPool and modification to ResBlock notebook
But now lets create model as mxresnet50 from fastai forums tread
Lets create mxresnet constructor.
mc = ModelConstructor(name='MxResNet')Then lets modify stem.
from model_constructor.xresnet import xresnet_stemmc.make_stem = xresnet_stem mc.stem_sizes = [3,32,64,64]Now lets change activation function to Mish. Here is link to forum discussion
 We'v got Mish is in model_constructor.activations, but from pytorch 1.9 take it from torch:
from torch.nn import Mishmc.act_fn = Mishmcoutput
MxResNet in_chans: 3, num_classes: 1000 expansion: 1, groups: 1, dw: False, div_groups: None act_fn: Mish, sa: False, se: False stem sizes: [3, 32, 64, 64], stride on 0 body sizes [64, 128, 256, 512] layers: [2, 2, 2, 2]
mc.print_changed_fields()output
Changed fields: name: MxResNet act_fn: Mish stem_sizes: [3, 32, 64, 64] make_stem: xresnet_stem
Here is model:
mc()output
MxResNet( act_fn: Mish, stem_sizes: [3, 32, 64, 64], make_stem: xresnet_stem (stem): Sequential( (conv_0): ConvBnAct( (conv): Conv2d(3, 3, kernel_size=(3, 3), stride=(2, 2), padding=(1, 1), bias=False) (bn): BatchNorm2d(3, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) (act_fn): Mish(inplace=True) ) (conv_1): ConvBnAct( (conv): Conv2d(3, 32, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(32, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) (act_fn): Mish(inplace=True) ) (conv_2): ConvBnAct( (conv): Conv2d(32, 64, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(64, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) (act_fn): Mish(inplace=True) ) (conv_3): ConvBnAct( (conv): Conv2d(64, 64, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(64, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) (act_fn): Mish(inplace=True) ) (stem_pool): MaxPool2d(kernel_size=3, stride=2, padding=1, dilation=1, ceil_mode=False) ) (body): Sequential( (l_0): Sequential( (bl_0): BasicBlock( (convs): Sequential( (conv_0): ConvBnAct( (conv): Conv2d(64, 64, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(64, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) (act_fn): Mish(inplace=True) ) (conv_1): ConvBnAct( (conv): Conv2d(64, 64, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(64, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) ) ) (act_fn): Mish(inplace=True) ) (bl_1): BasicBlock( (convs): Sequential( (conv_0): ConvBnAct( (conv): Conv2d(64, 64, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(64, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) (act_fn): Mish(inplace=True) ) (conv_1): ConvBnAct( (conv): Conv2d(64, 64, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(64, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) ) ) (act_fn): Mish(inplace=True) ) ) (l_1): Sequential( (bl_0): BasicBlock( (convs): Sequential( (conv_0): ConvBnAct( (conv): Conv2d(64, 128, kernel_size=(3, 3), stride=(2, 2), padding=(1, 1), bias=False) (bn): BatchNorm2d(128, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) (act_fn): Mish(inplace=True) ) (conv_1): ConvBnAct( (conv): Conv2d(128, 128, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(128, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) ) ) (id_conv): Sequential( (id_conv): ConvBnAct( (conv): Conv2d(64, 128, kernel_size=(1, 1), stride=(2, 2), bias=False) (bn): BatchNorm2d(128, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) ) ) (act_fn): Mish(inplace=True) ) (bl_1): BasicBlock( (convs): Sequential( (conv_0): ConvBnAct( (conv): Conv2d(128, 128, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(128, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) (act_fn): Mish(inplace=True) ) (conv_1): ConvBnAct( (conv): Conv2d(128, 128, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(128, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) ) ) (act_fn): Mish(inplace=True) ) ) (l_2): Sequential( (bl_0): BasicBlock( (convs): Sequential( (conv_0): ConvBnAct( (conv): Conv2d(128, 256, kernel_size=(3, 3), stride=(2, 2), padding=(1, 1), bias=False) (bn): BatchNorm2d(256, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) (act_fn): Mish(inplace=True) ) (conv_1): ConvBnAct( (conv): Conv2d(256, 256, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(256, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) ) ) (id_conv): Sequential( (id_conv): ConvBnAct( (conv): Conv2d(128, 256, kernel_size=(1, 1), stride=(2, 2), bias=False) (bn): BatchNorm2d(256, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) ) ) (act_fn): Mish(inplace=True) ) (bl_1): BasicBlock( (convs): Sequential( (conv_0): ConvBnAct( (conv): Conv2d(256, 256, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(256, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) (act_fn): Mish(inplace=True) ) (conv_1): ConvBnAct( (conv): Conv2d(256, 256, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(256, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) ) ) (act_fn): Mish(inplace=True) ) ) (l_3): Sequential( (bl_0): BasicBlock( (convs): Sequential( (conv_0): ConvBnAct( (conv): Conv2d(256, 512, kernel_size=(3, 3), stride=(2, 2), padding=(1, 1), bias=False) (bn): BatchNorm2d(512, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) (act_fn): Mish(inplace=True) ) (conv_1): ConvBnAct( (conv): Conv2d(512, 512, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(512, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) ) ) (id_conv): Sequential( (id_conv): ConvBnAct( (conv): Conv2d(256, 512, kernel_size=(1, 1), stride=(2, 2), bias=False) (bn): BatchNorm2d(512, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) ) ) (act_fn): Mish(inplace=True) ) (bl_1): BasicBlock( (convs): Sequential( (conv_0): ConvBnAct( (conv): Conv2d(512, 512, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(512, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) (act_fn): Mish(inplace=True) ) (conv_1): ConvBnAct( (conv): Conv2d(512, 512, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(512, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) ) ) (act_fn): Mish(inplace=True) ) ) ) (head): Sequential( (pool): AdaptiveAvgPool2d(output_size=1) (flat): Flatten(start_dim=1, end_dim=-1) (fc): Linear(in_features=512, out_features=1000, bias=True) ) )
Now lets make MxResNet50
mc.expansion = 4 mc.layers = [3,4,6,3] mc.name = "mxresnet50"mc.print_changed_fields()output
Changed fields: name: mxresnet50 layers: [3, 4, 6, 3] act_fn: Mish expansion: 4 stem_sizes: [3, 32, 64, 64] make_stem: xresnet_stem
Now we have mxresnet50 constructor.
 We can inspect every parts of it.
 And after call it we got model.
mcoutput
mxresnet50 in_chans: 3, num_classes: 1000 expansion: 4, groups: 1, dw: False, div_groups: None act_fn: Mish, sa: False, se: False stem sizes: [3, 32, 64, 64], stride on 0 body sizes [64, 128, 256, 512] layers: [3, 4, 6, 3]
mc.stem.conv_1output
ConvBnAct( (conv): Conv2d(3, 32, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(32, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) (act_fn): Mish(inplace=True) )
mc.body.l_0.bl_0output
BasicBlock( (convs): Sequential( (conv_0): ConvBnAct( (conv): Conv2d(64, 64, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(64, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) (act_fn): Mish(inplace=True) ) (conv_1): ConvBnAct( (conv): Conv2d(64, 64, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(64, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) ) ) (act_fn): Mish(inplace=True) )
We can get model direct way:
mc = ModelConstructor( name="MxResNet", act_fn=Mish, layers=[3,4,6,3], expansion=4, make_stem=xresnet_stem, stem_sizes=[32,64,64] ) model = mc()Another way:
model = ModelConstructor.create_model( name="MxResNet", act_fn=Mish, layers=[3,4,6,3], expansion=4, make_stem=xresnet_stem, stem_sizes=[32,64,64] )Now lets change Resblock to YaResBlock (Yet another ResNet, former NewResBlock) is in lib from version 0.1.0
from model_constructor.yaresnet import YaBasicBlockmc = ModelConstructor(name="YaResNet") mc.block = YaBasicBlockOr in one line:
mc = ModelConstructor(name="YaResNet", block=YaBasicBlock)That all. Now we have YaResNet constructor
mc.print_cfg()output
ModelConstructor( name='YaResNet' in_chans=3 num_classes=1000 block='YaBasicBlock' conv_layer='ConvBnAct' block_sizes=[64, 128, 256, 512] layers=[2, 2, 2, 2] norm='BatchNorm2d' act_fn='ReLU' expansion=1 groups=1 bn_1st=True zero_bn=True stem_sizes=[64] stem_pool="MaxPool2d {'kernel_size': 3, 'stride': 2, 'padding': 1}" init_cnn='init_cnn' make_stem='make_stem' make_layer='make_layer' make_body='make_body' make_head='make_head')  Let see what we have.
mc.body.l_1.bl_0output
YaBasicBlock( (reduce): ConvBnAct( (conv): Conv2d(64, 64, kernel_size=(1, 1), stride=(2, 2), bias=False) (bn): BatchNorm2d(64, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) (act_fn): ReLU(inplace=True) ) (convs): Sequential( (conv_0): ConvBnAct( (conv): Conv2d(64, 128, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(128, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) (act_fn): ReLU(inplace=True) ) (conv_1): ConvBnAct( (conv): Conv2d(128, 128, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1), bias=False) (bn): BatchNorm2d(128, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) ) ) (id_conv): ConvBnAct( (conv): Conv2d(64, 128, kernel_size=(1, 1), stride=(1, 1), bias=False) (bn): BatchNorm2d(128, eps=1e-05, momentum=0.1, affine=True, track_running_stats=True) ) (merge): ReLU(inplace=True) )
Lets create xResnet34 like model constructor:
from typing import Callable from model_constructor.helpers import ModSeq class YaResnet34(ModelConstructor): block: type[nn.Module] = YaBasicBlock layers: list[int] = [3, 4, 6, 3] make_stem: Callable[[ModelCfg], ModSeq] = xresnet_stemmc = YaResnet34() mc.print_cfg()output
YaResnet34( in_chans=3 num_classes=1000 block='YaBasicBlock' conv_layer='ConvBnAct' block_sizes=[64, 128, 256, 512] layers=[3, 4, 6, 3] norm='BatchNorm2d' act_fn='ReLU' expansion=1 groups=1 bn_1st=True zero_bn=True stem_sizes=[64] stem_pool="MaxPool2d {'kernel_size': 3, 'stride': 2, 'padding': 1}" init_cnn='init_cnn' make_stem='xresnet_stem' make_layer='make_layer' make_body='make_body' make_head='make_head')  And xResnet50 like model can be inherited from YaResnet34:
class YaResnet50(YaResnet34): expansion: int = 4mc = YaResnet50() mcoutput
YaResnet50 in_chans: 3, num_classes: 1000 expansion: 4, groups: 1, dw: False, div_groups: None act_fn: ReLU, sa: False, se: False stem sizes: [64], stride on 0 body sizes [64, 128, 256, 512] layers: [3, 4, 6, 3]