code: def _run(self, x, axes=None, keepdims=None):  # type: ignore
      axes = tuple(axes) if axes is not None else None
      res = np.sum(x, axis=axes, keepdims=keepdims, dtype=x.dtype)
      if keepdims == 0 and not isinstance(res, np.ndarray):
          # The runtime must return a numpy array of a single float.
          res = np.array(res)
      return (res,)
  
file_path: onnx/onnx/reference/ops/op_reduce_sum.py
imports: import numpy
  from onnx.reference.ops._op import OpRunReduceNumpy
label_desc: Use image node_id 1 for calling the ReduceSum_1 obj's underlying member method code with example usage: obj._run(x, axes, keepdims) and returns: res