class_docstr: MobileNetV1
  
  MobileNetV1 Backbone for RetinaFace.
code: def __init__(self):
      super().__init__()
      self.stage1 = nn.Sequential(
          conv_bn(3, 8, 2, leaky=0.1),  # 3
          conv_dw(8, 16, 1),  # 7
          conv_dw(16, 32, 2),  # 11
          conv_dw(32, 32, 1),  # 19
          conv_dw(32, 64, 2),  # 27
          conv_dw(64, 64, 1),  # 43
      )
      self.stage2 = nn.Sequential(
          conv_dw(64, 128, 2),  # 43 + 16 = 59
          conv_dw(128, 128, 1),  # 59 + 32 = 91
          conv_dw(128, 128, 1),  # 91 + 32 = 123
          conv_dw(128, 128, 1),  # 123 + 32 = 155
          conv_dw(128, 128, 1),  # 155 + 32 = 187
          conv_dw(128, 128, 1),  # 187 + 32 = 219
      )
      self.stage3 = nn.Sequential(
          conv_dw(128, 256, 2),  # 219 +3 2 = 241
          conv_dw(256, 256, 1),  # 241 + 64 = 301
      )
      self.avg = nn.AdaptiveAvgPool2d((1, 1))
      self.fc = nn.Linear(256, 1000)
  
imports: import torch
  from torch import nn
  from towhee.models.retina_face.utils import conv_dw, conv_bn
label_desc: Use image node_id 1 to create a new MobileNetV1 object from inherited base classes: nn with example: obj = MobileNetV1()