Plot rendering error: 'NoneType' object has no attribute 'dpi'; metadata = {'Entries': 153593, 'Name': 'SigmaTotDist-1', 'Overflow': 7.0, 'Type': 'Histo1d', 'Underflow': 0.0, 'x': {'AxisTitle': 'Sigma ToT [BC]', 'Bins': 101, 'High': 1.05, 'Low': -0.05}, 'y': {'AxisTitle': 'Number of Pixels'}, 'z': {'AxisTitle': 'z'}}