Traceback (most recent call last):


 "/Users/walter/pyvenvs/ipython-bad/lib/python3.8/site-packages/IPython/core/interactiveshell.py", line 3337, in run_ast_nodes

if (await self.run_code(code, result,
async_=asy)):


 "/Users/walter/pyvenvs/ipython-bad/lib/python3.8/site-packages/IPython/core/interactiveshell.py", line 3434, in run_code

self.showtraceback(running_compiled_code=True)


 "/Users/walter/pyvenvs/ipython-bad/lib/python3.8/site-packages/IPython/core/interactiveshell.py", line 2046, in showtraceback

stb = self.InteractiveTB.structured_traceback(etype,


 "/Users/walter/pyvenvs/ipython-bad/lib/python3.8/site-packages/IPython/core/ultratb.py", line 1435, in structured_traceback

return FormattedTB.structured_traceback(


 "/Users/walter/pyvenvs/ipython-bad/lib/python3.8/site-packages/IPython/core/ultratb.py", line 1335, in structured_traceback

return VerboseTB.structured_traceback(


 "/Users/walter/pyvenvs/ipython-bad/lib/python3.8/site-packages/IPython/core/ultratb.py", line 1192, in structured_traceback

formatted_exception = self.format_exception_as_a_whole(etype, evalue, etb, number_of_lines_of_context,


 "/Users/walter/pyvenvs/ipython-bad/lib/python3.8/site-packages/IPython/core/ultratb.py", line 1152, in format_exception_as_a_whole

frames = self.format_records(records, last_unique, recursion_repeat)


 "/Users/walter/pyvenvs/ipython-bad/lib/python3.8/site-packages/IPython/core/ultratb.py", line 891, in format_records

if r[0].f_locals.get("__tracebackhide__", 0):
AttributeError: 'list' object has no attribute 'get'

Traceback (most recent call last):


 "/home/karin/Documents/git/orange3venv/lib/python3.6/site-packages/orangecanvas/scheme/signalmanager.py", line 936, in __process_next

if self.__process_next_helper(use_max_active=True):


 "/home/karin/Documents/git/orange3venv/lib/python3.6/site-packages/orangecanvas/scheme/signalmanager.py", line 974, in __process_next_helper

self.process_node(selected_node)


 "/home/karin/Documents/git/orange3venv/lib/python3.6/site-packages/orangecanvas/scheme/signalmanager.py", line 605, in process_node

self.send_to_node(node, signals_in)


 "/home/karin/Documents/git/orange-widget-base/orangewidget/workflow/widgetsscheme.py", line 792, in send_to_node

self.process_signals_for_widget(node, widget, signals)


 "/home/karin/Documents/git/orange-widget-base/orangewidget/workflow/widgetsscheme.py", line 826, in process_signals_for_widget

handler(*args)


 "/home/karin/Documents/git/orange3/Orange/widgets/visualize/owheatmap.py", line 557, in set_dataset

self.update_heatmaps()


 "/home/karin/Documents/git/orange3/Orange/widgets/visualize/owheatmap.py", line 589, in update_heatmaps

self.construct_heatmaps_scene(parts, self.effective_data)


 "/home/karin/Documents/git/orange3/Orange/widgets/visualize/owheatmap.py", line 773, in construct_heatmaps_scene

self.setup_scene(parts, data)


 "/home/karin/Documents/git/orange3/Orange/widgets/visualize/owheatmap.py", line 796, in setup_scene

widget.setHeatmaps(parts)


 "/home/karin/Documents/git/orange3/Orange/widgets/visualize/utils/heatmap.py", line 450, in setHeatmaps

data=X_part, span=parts.span, colormap=colormap,


 "/home/karin/Documents/git/orange3/Orange/widgets/visualize/utils/heatmap.py", line 953, in __init__

self.setHeatmapData(data)


 "/home/karin/Documents/git/orange3/Orange/widgets/visualize/utils/heatmap.py", line 987, in setHeatmapData

self.__updatePixmap()


 "/home/karin/Documents/git/orange3/Orange/widgets/visualize/utils/heatmap.py", line 1020, in __updatePixmap

qimage = qimage_from_array(rgb)


 "/home/karin/Documents/git/orange3/Orange/widgets/utils/image.py", line 33, in qimage_from_array

buffer = img.bits().asarray(w * h * 4)
AttributeError: 'NoneType' object has no attribute 'asarray'
