old_contents: class Keystore:
      '''
      Keyring facade
  
      .. versionadded:: x.x.x
  
      '''
  
      def set_key(self, servicename, key, value, **kwargs):
          self._set_key(servicename, key, value, **kwargs)
  
      def _set_key(self, servicename, key, value, **kwargs):
          raise NotImplementedError()
  
      def get_key(self, servicename, key, **kwargs):
          return self._get_key(servicename, key)
  
      def _get_key(self, servicename, key, **kwargs):
          raise NotImplementedError()
  
new_contents: '''
  Keystore
  =======
  The :class:`Keystore` provides a mechanism for securing/storing cryptographic keys (such as user credentials) in a container. typically needed to support authentication APIs such as OAuth2
  .. note::
          Typically needed to support authentication APIs such as OAuth2
           
  Supported Platforms
  -------------------
  Android, iOS, Windows, OS X, Linux
  ---------------
  '''
  
  class Keystore:
      '''
      Keystore facade
      '''
  
      def set_key(self, servicename, key, value, **kwargs):
          self._set_key(servicename, key, value, **kwargs)
  
      def _set_key(self, servicename, key, value, **kwargs):
          raise NotImplementedError()
  
      def get_key(self, servicename, key, **kwargs):
          return self._get_key(servicename, key)
  
      def _get_key(self, servicename, key, **kwargs):
          raise NotImplementedError()
  
subject: Add Keystore docstring to correct keystore file