docstr: Gets the value of maxEpoch or its default value.
code: def getLearningRate(self):
      """
      Gets the value of maxEpoch or its default value.
      """
      return self.getOrDefault(self.learningRate)
  
imports: from pyspark.ml.pipeline import Estimator, Model
  from pyspark.ml.param.shared import *
  from bigdl.dllib.utils.common import *
  import sys
label_desc: Use image node_id 3 for calling the HasLearningRate obj's underlying member method code with example usage: obj.getLearningRate() and returns: self