'Internal implementation to set property values, that is used
by __set__, set_from_json, etc.
Args:
obj (HasProps)
The object the property is being set on.
old (obj) :
The previous value of the property to compare
setter (ClientSession or ServerSession or None, optional) :
This is used to prevent "boomerang" updates to Bokeh apps.
(default: None)
In the context of a Bokeh server application, incoming updates
to properties will be annotated with the session that is
doing the updating. This value is propagated through any
subsequent change notifications that the update triggers.
The session can compare the event setter to itself, and
suppress any updates that originate from itself.
Raises:
NotImplementedError
**Subclasses must implement this to serve their specific needs.**'

def _internal_set(self, obj, value, setter=None):

    raise NotImplementedError('Implement    _internal_set()')
