Drop requirement for NdMapping to be defined with OrderedDict (#5867)

Co-authored-by: Simon Høxbro Hansen <simon.hansen@me.com>

holoviews/core/ndmapping.py

@@ -104,10 +104,6 @@ def __init__(self, initial_items=None, kdims=None, **params):
         if kdims is not None:
             params['kdims'] = kdims
         super().__init__(OrderedDict(), **dict(params))
-        if type(initial_items) is dict and not self.sort:
-            raise ValueError('If sort=False the data must define a fixed '
-                             'ordering, please supply a list of items or '
-                             'an OrderedDict, not a regular dictionary.')
 
         self._next_ind = 0
         self._check_key_type = True

holoviews/element/tabular.py

@@ -41,10 +41,8 @@ def cols(self):
     def __init__(self, data, **params):
         if data is None:
             data = []
-        if type(data) == dict:
-            raise ValueError("ItemTable cannot accept a standard Python  dictionary "
-                             "as a well-defined item ordering is required.")
-        elif isinstance(data, dict): pass
+        if isinstance(data, dict):
+            pass
         elif isinstance(data, list):
             data = OrderedDict(data)
         else: