parameters: (self)
docstring: Aggregate all existing evaluation results in the memory, and return the overall
          performance across different mini-batches.
  
          Args:
              None
  
          Returns:
              The overall performance across different mini-batches.
  
          Return types:
              float|list(float)|numpy.array: the metrics via Python.
docstring_summary: Aggregate all existing evaluation results in the memory, and return the overall
          performance across different mini-batches.
docstring_tokens: Aggregate all existing evaluation results in the memory and return the overall performance across different mini - batches .
function: def eval(self):
          """
          Aggregate all existing evaluation results in the memory, and return the overall
          performance across different mini-batches.
  
          Args:
              None
  
          Returns:
              The overall performance across different mini-batches.
  
          Return types:
              float|list(float)|numpy.array: the metrics via Python.
          """
          raise NotImplementedError(
              "Should not use it directly, please extend it.")
function_tokens: def eval ( self ) : raise NotImplementedError ( "Should not use it directly, please extend it." )