old_contents: """The device class used to represent a particular function of an accelerator
  element.
  
  A physical element in an accelerator may have multiple devices: an example at
  DLS is a sextupole magnet that contains also horizontal and vertical corrector
  magnets and a skew quadrupole.
  """
  
  
  class Device(object):
      """A representation of a property of an element associated with a field.
  
      Typically a control system will be used to set and get values on a
      device.
      """
      def is_enabled(self):
          """Whether the device is enabled.
  
          Returns:
              bool: whether the device is enabled.
          """
          raise NotImplementedError()
  
      def set_value(self, value):
          """Set the value on the device.
  
          Args:
              value (float): the value to set.
          """
          raise NotImplementedError()
  
      def get_value(self):
          """Read the value from the device.
  
          Returns:
              float: the value of the PV.
          """
          raise NotImplementedError()
  
  
  class BasicDevice(Device):
      """A basic implementation of the device class. This device does not have a
          pv associated with it, nor does it interact with a simulator. In short
          this device acts as simple storage for data that rarely changes, as it is
          not affected by changes to other aspects of the accelerator.
      """
      def __init__(self, value, enabled=True):
          """Args:
              value (?): can be a number or a list of numbers.
              enabled (bool-like): Whether the device is enabled. May be a
                                    PvEnabler object.
          """
          self.value = value
          self._enabled = enabled
  
      def is_enabled(self):
          """Whether the device is enabled.
  
          Returns:
              bool: whether the device is enabled.
          """
          return bool(self._enabled)
  
      def set_value(self, value):
          """Set the value on the device.
  
          Args:
              value (?): the value to set.
          """
          self.value = value
  
      def get_value(self):
          """Read the value from the device.
  
          Returns:
              ?: the value of the PV.
          """
          return self.value
  
new_contents: """The device class used to represent a particular function of an accelerator
  element.
  
  A physical element in an accelerator may have multiple devices: an example at
  DLS is a sextupole magnet that contains also horizontal and vertical corrector
  magnets and a skew quadrupole.
  """
  
  
  class Device(object):
      """A representation of a property of an element associated with a field.
  
      Typically a control system will be used to set and get values on a
      device.
      """
      def is_enabled(self):
          """Whether the device is enabled.
  
          Returns:
              bool: whether the device is enabled.
          """
          raise NotImplementedError()
  
      def set_value(self, value):
          """Set the value on the device.
  
          Args:
              value (float): the value to set.
          """
          raise NotImplementedError()
  
      def get_value(self):
          """Read the value from the device.
  
          Returns:
              float: the value of the PV.
          """
          raise NotImplementedError()
  
  
  class BasicDevice(Device):
      """A basic implementation of the device class. This device does not have a
          pv associated with it, nor does it interact with a simulator. In short
          this device acts as simple storage for data that rarely changes, as it is
          not affected by changes to other aspects of the accelerator.
      """
      def __init__(self, value, enabled=True):
          """Args:
              value (?): can be a number or a list of numbers.
              enabled (bool-like): Whether the device is enabled. May be a
                                    PvEnabler object.
          """
          self.value = value
          self._enabled = enabled
  
      def is_enabled(self):
          """Whether the device is enabled.
  
          Returns:
              bool: whether the device is enabled.
          """
          return bool(self._enabled)
  
      def set_value(self, value):
          """Set the value on the device.
  
          Args:
              value (?): the value to set.
          """
          self.value = value
  
      def get_value(self, handle=None):
          """Read the value from the device.
  
          Returns:
              ?: the value of the PV.
          """
          return self.value
  
subject: Make basic devices work when passed a handle.