class_docstr: Base class for tuning job or training job analytics classes.
  
  Understands common functionality like persistence and caching.
docstr: Persists the analytics dataframe to a file.
  
  Args:
      filename (str): The name of the file to save to.
docstr_tok: ["Persists","the","analytics","dataframe","to","a","file",".","Args",":","filename","(","str",")",":","The","name","of","the","file","to","save","to","."]
code: def export_csv(self, filename):
      """Persists the analytics dataframe to a file.
  
      Args:
          filename (str): The name of the file to save to.
      """
      self.dataframe().to_csv(filename)
  
imports: from __future__ import print_function, absolute_import
  from abc import ABCMeta, abstractmethod
  from collections import defaultdict, OrderedDict
  import datetime
  import logging
  from six import with_metaclass
  from sagemaker.session import Session
  from sagemaker.utils import DeferredError
  from sagemaker.lineage import artifact
label_desc: Use image node_id 2 for calling the AnalyticsMetricsBase obj's underlying member method code with example usage: obj.export_csv(filename) without return types