Dynamically updating graphs based on real-time data using matplotlib

from time import sleep
from threading importThread
import numpy as np
import  as plt
from  importButton
fig, ax = ()
# Setting the graphic display position
plt.subplots_adjust(bottom=0.2)
# Experimental data
range_start, range_end, range_step =0,1,0.005
t = (range_start, range_end, range_step)
s = (4**t)
l,= (t, s, lw=2)
# Custom class to encapsulate the two button click event handlers
classButtonHandler:
def __init__(self):
 =True
self.range_s, self.range_e, self.range_step =0,1,0.005
# Threaded functions to update data and redraw graphs
def threadStart(self):
while :
sleep(0.02)
self.range_s += self.range_step
self.range_e += self.range_step
t = (self.range_s, self.range_e, self.range_step)
ydata = (4**t)
#Update data
l.set_xdata(t-t[0])
l.set_ydata(ydata)
#Redraw the graph
()
defStart(self, event):
 =True
#Create and start a new thread
t =Thread(target=)
()
defStop(self, event):
 =False
callback =ButtonHandler()
# Create the button and set the click event handler function
axprev = ([0.81,0.05,0.1,0.075])
bprev =Button(axprev,'Stop')
bprev.on_clicked()
axnext = ([0.7,0.05,0.1,0.075])
bnext =Button(axnext,'Start')
bnext.on_clicked()
()