old_contents: # Licensed under the Apache License, Version 2.0 (the "License"); you may
  # not use this file except in compliance with the License. You may obtain
  # a copy of the License at
  #
  #      http://www.apache.org/licenses/LICENSE-2.0
  #
  # Unless required by applicable law or agreed to in writing, software
  # distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
  # WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
  # License for the specific language governing permissions and limitations
  # under the License.
  
  import yaml
  
  
  if hasattr(yaml, 'CSafeDumper'):
      yaml_dumper = yaml.CSafeDumper
  else:
      yaml_dumper = yaml.SafeDumper
  
  
  def load(s):
      try:
          yml_dict = yaml.safe_load(s)
      except yaml.YAMLError as exc:
          msg = 'An error occurred during YAML parsing.'
          if hasattr(exc, 'problem_mark'):
              msg += ' Error position: (%s:%s)' % (exc.problem_mark.line + 1,
                                                   exc.problem_mark.column + 1)
          raise ValueError(msg)
      if not isinstance(yml_dict, dict) and not isinstance(yml_dict, list):
          raise ValueError('The source is not a YAML mapping or list.')
      if isinstance(yml_dict, dict) and len(yml_dict) < 1:
          raise ValueError('Could not find any element in your YAML mapping.')
      return yml_dict
  
  
  def dump(s):
      return yaml.dump(s, Dumper=yaml_dumper)
  
new_contents: # Licensed under the Apache License, Version 2.0 (the "License"); you may
  # not use this file except in compliance with the License. You may obtain
  # a copy of the License at
  #
  #      http://www.apache.org/licenses/LICENSE-2.0
  #
  # Unless required by applicable law or agreed to in writing, software
  # distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
  # WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
  # License for the specific language governing permissions and limitations
  # under the License.
  
  import yaml
  
  
  def load(s):
      try:
          yml_dict = yaml.safe_load(s)
      except yaml.YAMLError as exc:
          msg = 'An error occurred during YAML parsing.'
          if hasattr(exc, 'problem_mark'):
              msg += ' Error position: (%s:%s)' % (exc.problem_mark.line + 1,
                                                   exc.problem_mark.column + 1)
          raise ValueError(msg)
      if not isinstance(yml_dict, dict) and not isinstance(yml_dict, list):
          raise ValueError('The source is not a YAML mapping or list.')
      if isinstance(yml_dict, dict) and len(yml_dict) < 1:
          raise ValueError('Could not find any element in your YAML mapping.')
      return yml_dict
  
  
  def dump(s):
      return yaml.safe_dump(s)
  
subject: Replace yaml.dump with yaml.safe_dump