code: def formatted_message(self):
          
          return render_template_string(
              self.body,
              event=self,
              meta=self.meta,
              original=self.original,
              updated=self.updated,
              version=self.version,
          )
docs: Method that will return the formatted message for the event.
  
          This formatting is done with Jinja and the template text is stored in
          the ``body`` attribute. The template is supplied the following
          variables, as well as the built in Flask ones:
  
          - ``event``: This is the event instance that this method belongs to.
          - ``meta``: This is a dictionary of cached values that have been stored
            when the event was created based upon the event's DSL.
          - ``original``: This is a dump of the instance before the instance was
            updated.
          - ``updated``: This is a dump of the instance after it was updated.
          - ``version``: This is the version of the event DSL.
  
          This property is cached because Jinja rendering is slower than raw
          Python string formatting.