Add _validators property for backward compatibility

Author: jonmmease

packages/python/plotly/plotly/basedatatypes.py

@@ -3019,11 +3019,47 @@ def __init__(self, plotly_name, **kwargs):
         # properties is modified
         self._change_callbacks = {}
 
+        # ### Backing property for backward compatible _validator property ##
+        self.__validators = None
+
     def _get_validator(self, prop):
         from .validator_cache import ValidatorCache
 
         return ValidatorCache.get_validator(self._path_str, prop)
 
+    @property
+    def _validators(self):
+        """
+        Validators used to stored in a private _validators property. This was
+        eliminated when we switched to building validators on demand using the
+        _get_validator method.
+
+        This property returns a simple object that
+
+        Returns
+        -------
+        dict-like interface for accessing the object's validators
+        """
+        obj = self
+        if self.__validators is None:
+            class ValidatorCompat(object):
+                def __getitem__(self, item):
+                    return obj._get_validator(item)
+
+                def __contains__(self, item):
+                    return obj.__contains__(item)
+
+                def __iter__(self):
+                    return iter(obj)
+
+                def items(self):
+                    return [(k, self[k]) for k in self]
+
+            self.__validators = ValidatorCompat()
+
+        return self.__validators
+
+
     def _process_kwargs(self, **kwargs):
         """
         Process any extra kwargs that are not predefined as constructor params