Potential fix to conversion bug

Author: marthacryan

packages/python/plotly/_plotly_utils/basevalidators.py

@@ -1,6 +1,7 @@
 import base64
 import numbers
 import textwrap
+import traceback
 import uuid
 from importlib import import_module
 import copy
@@ -488,9 +489,10 @@ def description(self):
         )
 
     def validate_coerce(self, v):
-
         if is_none_or_typed_array_spec(v):
             pass
+        elif 'layer' in self.parent_name or 'range' in self.parent_name or 'geojson' in self.parent_name:
+            v = to_scalar_or_list(v)
         elif is_homogeneous_array(v):
             v = to_typed_array_spec(v)
         elif is_simple_array(v):

packages/python/plotly/plotly/tests/test_optional/test_graph_objs/test_skipped_b64_keys.py

@@ -70,7 +70,7 @@ def test_np_layers(self):
 
         # TODO: This is failing because the actual value of the "dash" field
         # is converted to the { b64, dtype } object.
-        # assert fig.layout['mapbox']['layers'][0]['line']['dash'] == (2.5, 1)
+        assert fig.layout['mapbox']['layers'][0]['line']['dash'] == (2.5, 1)
 
         assert (
             fig.layout["mapbox"]["layers"][0]["source"]["features"][0]["geometry"][