new_contents: #!/usr/bin/env python3
  # -*- coding: UTF-8 -*-
  
  # Copyright 2017 Eddie Antonio Santos <easantos@ualberta.ca>
  #
  # 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.
  
  """
  Miscellaneous utilities.
  """
  
  
  from typing import Type, TypeVar
  
  
  C = TypeVar('C')
  
  
  def singleton(cls: Type[C]) -> C:
      """
      Given a class, instantiates it. To be used as a decorator to create
      psuedo-singletons.
      """
      return cls()
  
  
  def test_singleton() -> None:
      class Foo:
          baz = 'quux'
  
      @singleton
      class bar(Foo):
          baz = 'fizz'
  
      assert isinstance(bar, Foo)
      assert bar.baz == 'fizz'
  
subject: Create singleton utility.