class_docstr: The class that stores and transmits data in neural networks.
      
docstr: Takes elementwise negative of the blob.
          
docstr_tok: ["Takes","elementwise","negative","of","the","blob","."]
code: def __neg__(self):
      """Takes elementwise negative of the blob."""
      if self.size == 0:
          raise ValueError("The blobs mustn't be empty.")
      return Blob(PythonWrapper.blob_neg(self._internal))
  
imports: import neoml
  import neoml.PythonWrapper
  import neoml.MathEngine
  import numpy
label_desc: Use image node_id 24 for calling the Blob obj's underlying member method code with example usage: obj.__neg__() and returns: Blob