How to avoid two windows from this tkinter code?

Question

The python code below was provided by NMech here.

import matplotlib.pyplot as plt
from matplotlib.backends.backend_tkagg import FigureCanvasTkAgg
import tkinter as tk
import numpy as np
class Application(tk.Frame):
 def __init__(self, master):
 tk.Frame.__init__(self,master)
 self.createWidgets()
 
 def createWidgets(self):
 fig = plt.figure(figsize=(8,8))
 ax = fig.add_axes([0.1,0.1,0.8,0.8], polar=True)
 canvas = FigureCanvasTkAgg(fig, master=root)
 canvas.get_tk_widget().grid(row=0,column=1)
 self.plotbutton = tk.Button(master=root, text="plot", command=lambda: self.plot(canvas, ax))
 self.plotbutton.grid(row=0, column=0)
 def plot(self, canvas, ax):
 c= ['r','b','g']
 ax.clear()
 for i in range(3):
 theta = np.random.uniform(0,360,10)
 r = np.random.uniform(0,1,10)
 ax.plot(theta,r,linestyle="None",marker='o',color=c[i])
 canvas.draw()
root=tk.Tk()
app=Application(master=root)
app.mainloop()

The code displays two similar windows shown below. One window is the app labeled 'tk', and the second window is labeled 'Figure 1'. How do I modify the code so it only displays the app 'tk'?

two-windows

• AshhadDevLab: Hi there @TedErsek, I just tried your code, mine is just showing a single window with label tk?
• RuthC: I also don't get the "Figure 1" but I found the python process does not end when I close the tk window. I tried replacing fig = plt.figure with fig = matplotlib.figure.Figure, then it worked as expected. As I understand it, pyplot always does window management for you but in this case you are organising that for yourself so you don't want to use pyplot at all.