code: def neg(a):
      """Returns the negative of a blob or a number."""
      return -a
  
imports: import neoml
  import neoml.PythonWrapper
  from neoml.MathEngine import MathEngine
  from neoml.Blob import Blob
  import numpy
label_desc: Use image node_id 10 for calling a global function with example usage: neg(a) and returns: unknown