code: def get_stem_fun(stem_type):
      """Retrieves the stem function by name."""
      stem_funs = {
          "res_stem_cifar": ResStemCifar,
          "res_stem_in": ResStem,
          "simple_stem_in": SimpleStem,
      }
      err_str = "Stem type '{}' not supported"
      assert stem_type in stem_funs.keys(), err_str.format(stem_type)
      return stem_funs[stem_type]
  
imports: from pycls.core.config import cfg
  from pycls.models.blocks import activation, conv2d, conv2d_cx, gap2d, gap2d_cx, init_weights, linear, linear_cx, norm2d, norm2d_cx, pool2d, pool2d_cx, SE
  from torch.nn import Module
label_desc: Use image node_id 1 for calling a global function with example usage: get_stem_fun(stem_type) and returns: stem_funs