The problem I have is:
Traceback (most recent call last):
File “/home/serge/.gramps/gramps51/plugins/LifeLineChartView/lifelinechart.py”, line 69, in
from life_line_chart import AncestorChart, DescendantChart
File “/home/serge/.gramps/gramps51/plugins/LifeLineChartView/life_line_chart-1.7.5/life_line_chart/AncestorChart.py”, line 7, in
from .BaseSVGChart import BaseSVGChart
File “/home/serge/.gramps/gramps51/plugins/LifeLineChartView/life_line_chart-1.7.5/life_line_chart/BaseSVGChart.py”, line 11, in
from .BaseChart import BaseChart
File “/home/serge/.gramps/gramps51/plugins/LifeLineChartView/life_line_chart-1.7.5/life_line_chart/BaseChart.py”, line 6, in
from .GraphicalFamily import GraphicalFamily
File “/home/serge/.gramps/gramps51/plugins/LifeLineChartView/life_line_chart-1.7.5/life_line_chart/GraphicalFamily.py”, line 1, in
from .Exceptions import LifeLineChartUnknownPlacementError, LifeLineChartUnknownSelectionAndConnectionError
ImportError: cannot import name ‘LifeLineChartUnknownPlacementError’