Traceback (most recent call last):


 "/home/whot/code/ratbag/piper/piper/application.py", line 52, in do_activate

window = Window(self._ratbag, application=self)


 "/home/whot/code/ratbag/piper/piper/window.py", line 57, in __init__

capabilities = self._device.capabilities
AttributeError: 'NoneType' object has no attribute 'capabilities'

Traceback (most recent call last):


 "/usr/local/lib/python3.6/site-packages/flask/app.py", line 1982, in wsgi_app

response = self.full_dispatch_request()


 "/usr/local/lib/python3.6/site-packages/flask/app.py", line 1614, in full_dispatch_request

rv = self.handle_user_exception(e)


 "/usr/local/lib/python3.6/site-packages/flask/app.py", line 1517, in handle_user_exception

reraise(exc_type, exc_value, tb)


 "/usr/local/lib/python3.6/site-packages/flask/_compat.py", line 33, in reraise

raise value


 "/usr/local/lib/python3.6/site-packages/flask/app.py", line 1612, in full_dispatch_request

rv = self.dispatch_request()


 "/usr/local/lib/python3.6/site-packages/flask/app.py", line 1598, in dispatch_request

return self.view_functions[rule.endpoint](**req.view_args)


 "/usr/local/lib/python3.6/site-packages/fava/application.py", line 264, in report

return render_template('{}.html'.format(report_name))


 "/usr/local/lib/python3.6/site-packages/flask/templating.py", line 134, in render_template

context, ctx.app)


 "/usr/local/lib/python3.6/site-packages/flask/templating.py", line 116, in _render

rv = template.render(context)


 "/usr/local/lib/python3.6/site-packages/jinja2/asyncsupport.py", line 76, in render

return original_render(self, *args, **kwargs)


 "/usr/local/lib/python3.6/site-packages/jinja2/environment.py", line 1008, in render

return self.environment.handle_exception(exc_info, True)


 "/usr/local/lib/python3.6/site-packages/jinja2/environment.py", line 780, in handle_exception

reraise(exc_type, exc_value, tb)


 "/usr/local/lib/python3.6/site-packages/jinja2/_compat.py", line 37, in reraise

raise value.with_traceback(tb)


 "/usr/local/lib/python3.6/site-packages/fava/templates/income_statement.html", line 3, in top-level template code

{% import '_tree_table.html' as tree_table with context %}


 "/usr/local/lib/python3.6/site-packages/fava/templates/_layout.html", line 43, in top-level template code

{% block content %}{% endblock %}


 "/usr/local/lib/python3.6/site-packages/fava/templates/income_statement.html", line 8, in block "content"

{{ charts.interval_totals(interval, (ledger.options['name_income'], ledger.options['name_expenses']), label=_('Net Profit')) }}


 "/usr/local/lib/python3.6/site-packages/jinja2/runtime.py", line 553, in _invoke

rv = self._func(*arguments)


 "/usr/local/lib/python3.6/site-packages/fava/templates/_charts.html", line 15, in template

{% do chart_data.append({


 "/usr/local/lib/python3.6/site-packages/fava/util/__init__.py", line 27, in wrapper

return list(func(*args, **kwargs))


 "/usr/local/lib/python3.6/site-packages/fava/core/charts.py", line 106, in interval_totals

'totals': _inventory_cost_or_value(inventory, end),


 "/usr/local/lib/python3.6/site-packages/fava/core/charts.py", line 49, in _inventory_cost_or_value

inventory = cost_or_value(inventory, date)


 "/usr/local/lib/python3.6/site-packages/fava/template_filters.py", line 41, in cost_or_value

return inventory.reduce(convert.get_cost)
AttributeError: 'Inventory' object has no attribute 'reduce'
