Style fix and docstring for the APM QA Python tool

webrtc/modules/audio_processing/test/py_quality_assessment/apm_quality_assessment.py

 #!/usr/bin/env python
 # Copyright (c) 2017 The WebRTC project authors. All Rights Reserved.
 #
 # Use of this source code is governed by a BSD-style license
 # that can be found in the LICENSE file in the root of the source
 # tree. An additional intellectual property rights grant can be found
 # in the file PATENTS.  All contributing project authors may
 # be found in the AUTHORS file in the root of the source tree.
 
 """Perform APM module quality assessment on one or more input files using one or
@@ skipping 14 matching lines @@
 import quality_assessment.noise_generation as noise_generation
 import quality_assessment.simulation as simulation
 
 _NOISE_GENERATOR_CLASSES = noise_generation.NoiseGenerator.REGISTERED_CLASSES
 _NOISE_GENERATORS_NAMES = _NOISE_GENERATOR_CLASSES.keys()
 _EVAL_SCORE_WORKER_CLASSES = eval_scores.EvaluationScore.REGISTERED_CLASSES
 _EVAL_SCORE_WORKER_NAMES = _EVAL_SCORE_WORKER_CLASSES.keys()
 
 _DEFAULT_CONFIG_FILE = 'apm_configs/default.json'
 
-def _instance_arguments_parser():
+
+def _InstanceArgumentsParser():
+  """Arguments parser factory.
+  """
   parser = argparse.ArgumentParser(description=(
       'Perform APM module quality assessment on one or more input files using '
       'one or more audioproc_f configuration files and one or more noise '
       'generators.'))
 
   parser.add_argument('-c', '--config_files', nargs='+', required=False,
                       help=('path to the configuration files defining the '
                             'arguments with which the audioproc_f tool is '
                             'called'),
                       default=[_DEFAULT_CONFIG_FILE])
@@ skipping 23 matching lines @@
   parser.add_argument('--air_db_path', required=True,
                       help='path to the Aechen IR database')
 
   return parser
 
 
 def main():
   # TODO(alessiob): level = logging.INFO once debugged.
   logging.basicConfig(level=logging.DEBUG)
 
-  parser = _instance_arguments_parser()
+  parser = _InstanceArgumentsParser()
   args = parser.parse_args()
 
   simulator = simulation.ApmModuleSimulator(
       aechen_ir_database_path=args.air_db_path,
       polqa_tool_path=args.polqa_path)
-  simulator.run(
+  simulator.Run(
       config_filepaths=args.config_files,
       input_filepaths=args.input_files,
       noise_generator_names=args.noise_generators,
       eval_score_names=args.eval_scores,
       output_dir=args.output_dir)
 
   sys.exit(0)
 
 
 if __name__ == '__main__':
   main()