code: def _log1p_exp_transform(self, expr):
      return ast.Log1pExpr(ast.ExpExpr(expr))
  
imports: import json
  import math
  import numpy
  from m2cgen import ast
  from m2cgen.assemblers import utils
  from m2cgen.assemblers.base import ModelAssembler
  from m2cgen.assemblers.linear import _linear_to_ast
label_desc: Use image node_id 8 for calling the LightGBMModelAssembler obj's underlying member method code with example usage: obj._log1p_exp_transform(expr) and returns: ast