code: def softmax(x: np.ndarray, axis: int = -1) -> np.ndarray:
      x_max = np.max(x, axis=axis, keepdims=True)
      tmp = np.exp(x - x_max)
      s = np.sum(tmp, axis=axis, keepdims=True)
      return tmp / s
  
file_path: onnx/onnx/backend/test/case/node/softmax.py
imports: import numpy
  import onnx
  from onnx.backend.test.case.base import Base
  from onnx.backend.test.case.node import expect
label_desc: Use image node_id 1 for calling a global function with example usage: softmax(x, axis) and returns: unknown