class_docstr: Compute precision / recall in binary classification, given the
  prediction vector and the label vector.
code: def _on_fetches(self, outputs):
      pred, label = outputs
      self.stat.feed(pred, label)
  
imports: import numpy
  from abc import ABCMeta
  import six
  from ..tfutils.common import get_op_tensor_name
  from ..utils import logger
  from ..utils.stats import BinaryStatistics, RatioCounter
  from .base import Callback
label_desc: Use image node_id 4 for calling the BinaryClassificationStats obj's underlying member method code with example usage: obj._on_fetches(outputs) without return types