Plotting data from arduino sensor (getting no plots although it gives me no error)

Dash Python
1

import dash
from dash.dependencies import Output, Event
import dash_core_components as dcc
import dash_html_components as html

import plotly
import plotly.graph_objs as go

import numpy as np
from time import time
import serial

from collections import deque

x = deque(maxlen=20)
y = deque(maxlen=20)
x.append(1) #initial starting data for x
y.append(1) #initial starting data for y

app = dash.Dash(name)
app.layout =html.Div(
[
dcc.Graph(id=‘live-graph’, animate =True),
dcc.Interval(
id=‘graph-update’, #the event (fct) that will update the page
interval=100 #and it will occure every 100ms
)

    ]
)

@app.callback(Output(‘live-graph’, ‘figure’),
events = [Event(‘graph-update’, ‘interval’)])

def update_graph():
global x
global y

ser = serial.Serial('COM3', 9600)
start_time = time()
timepoints = []
y = []
#apdate data
y.append(float(data[0])*5.0/1024)
timepoints.append(time()-start_time)
x = timepoints[-1]

data = go.Scatter(
    x = list(x),
    y = list(y),

    name = 'Scatter',
    mode = 'lines+markers'
    )
return {'data' : [data], 'layout': go.Layout(xaxis = dict(range=[min(x),max(x)]),
                                             yaxis = dict(range=[min(y),max(y)])
                                                          ) }

if name == ‘main’:
app.run_server(debug=True)