parameters: (self, referer)
docstring: Add an object that is referencing this sprite.
docstring_summary: Add an object that is referencing this sprite.
docstring_tokens: Add an object that is referencing this sprite .
function: def add_reference(self, referer):
          """
          Add an object that is referencing this sprite.
          """
          self._refs.append(referer)
function_tokens: def add_reference ( self , referer ) : self . _refs . append ( referer )