class_docstr: Compute precision / recall in binary classification, given the
  prediction vector and the label vector.
code: def _after_inference(self):
      return {
          self.prefix + "_precision": self.stat.precision,
          self.prefix + "_recall": self.stat.recall,
      }
  
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 5 for calling the BinaryClassificationStats obj's underlying member method code with example usage: obj._after_inference() and returns: dict