Trouble placing line on a bar graph

Trying to place a line on a graph as so:

graph_quality_coverage = dcc.Graph( id=‘quality_coverage’, figure={
‘data’: [trace_quality_coverage],
‘layout’:
go.Layout(title=‘Code Coverage’, titlefont=dict(size=25, color=’#000000’), barmode=‘grouped’, margin = dict(b = ‘275’), height=scale*1800, yaxis=dict(title=‘Coverage’, tickformat=’,.0%’, range=[0,1]), xaxis=dict(tickangle=45),shapes=[dict(type=‘line’,xref=‘paper’,yref=‘paper’,x0=0,x1=1,y0=0,y1=1)],line=dict(color=‘rgb(50, 171, 96)’,width=‘4’,dash=‘dashdot’))
})

returns:

File “/usr/local/lib/python2.7/site-packages/plotly/graph_objs/graph_objs.py”, line 377, in init
self.setitem(key, val, _raise=_raise)
File “/usr/local/lib/python2.7/site-packages/plotly/graph_objs/graph_objs.py”, line 428, in setitem
raise exceptions.PlotlyDictKeyError(self, path)
plotly.exceptions.PlotlyDictKeyError: ‘line’ is not allowed in ‘layout’

Path To Error: [‘line’]

Valid attributes for ‘layout’ at path [] under parents []:

Belay this question. the answer is:
[(dict(type=‘line’, xref=‘paper’, yref=‘paper’, x0=0, x1=1, y0=0.9, y1=0.9, line=dict(color=’#000000’, width=3)))]
I don’t see how to close this, but that would be appropriate.