old_contents: #!/usr/bin/env python
  # coding=utf-8
  
  
  class classproperty(object):
      def __init__(self, attr):
          self.attr = attr
  
      def __get__(self, _, owner):
          return self.attr(owner)
  
new_contents: #!/usr/bin/env python
  # coding=utf-8
  """
  Pubmed Utilities.
  """
  
  
  # noinspection PyPep8Naming
  class classproperty(object):
      """Decorator.  Define class property."""
  
      def __init__(self, attr):
          self.attr = attr
  
      def __get__(self, _, owner):
          return self.attr(owner)
  
subject: document pubmed utils