old_contents: """Copyright 2013 Google Inc. All Rights Reserved.
  
  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 inspect
  import sys
  
  
  ALL_IMPORTED_MODULES = object()
  
  
  def find_classes(modules, classes):
      if classes is not None:
          all_classes = set(classes)
      else:
          all_classes = set()
      for module in _get_explicit_or_default_modules(modules):
          # TODO(kurts): how is a module getting to be None??
          if module is not None:
              all_classes |= _find_classes_in_module(module)
      return all_classes
  
  
  def _get_explicit_or_default_modules(modules):
      if modules is ALL_IMPORTED_MODULES:
          return list(sys.modules.values())
      elif modules is None:
          return []
      return modules
  
  
  def _find_classes_in_module(module):
      classes = set()
      for member_name, member in inspect.getmembers(module):
          try:
              if inspect.isclass(member) and not member_name == '__class__':
                  classes.add(member)
          except NameError:
              # In Python 3 calling isinstance() on SWIG's global cvar property
              # raises:
              #     "NameError: Unknown C global variable"
              # In that case just continue, otherwise let the Error through.
              if not member_name == 'cvar':
                  raise
      return classes
  
new_contents: """Copyright 2013 Google Inc. All Rights Reserved.
  
  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 inspect
  import sys
  
  
  ALL_IMPORTED_MODULES = object()
  
  
  def find_classes(modules, classes):
      if classes is not None:
          all_classes = set(classes)
      else:
          all_classes = set()
      for module in _get_explicit_or_default_modules(modules):
          # TODO(kurts): how is a module getting to be None??
          if module is not None:
              all_classes |= _find_classes_in_module(module)
      return all_classes
  
  
  def _get_explicit_or_default_modules(modules):
      if modules is ALL_IMPORTED_MODULES:
          return list(sys.modules.values())
      elif modules is None:
          return []
      return modules
  
  
  def _find_classes_in_module(module):
      classes = set()
  
      try:
          # Libraries such as tensorflow return __bases__ as an integer
          # which the inspect.getmembers() function attemps to iterate through
          if not isinstance(module.__bases__, tuple):
              module.__bases__ = []
      except AttributeError:
          pass
  
      for member_name, member in inspect.getmembers(module):
          try:
              if inspect.isclass(member) and not member_name == '__class__':
                  classes.add(member)
          except NameError:
              # In Python 3 calling isinstance() on SWIG's global cvar property
              # raises:
              #     "NameError: Unknown C global variable"
              # In that case just continue, otherwise let the Error through.
              if not member_name == 'cvar':
                  raise
      return classes
  
subject: handle find_classes_in_module when .__bases__ is not a tuple