[Python] Clearing a subplot to update with a new one

I have some radiobuttons to select colour and width of a linestring in an embedded plot. I can't get the plot to clear when I select a new colour or width and the new plot is placed below the original plot. I have probably complicated things by using tkinter, matplotlib and shapely. I have been successful in destroying the entire window and rebuilidng it but it seemed pretty clunky. How can I remove the old plot or figure so I can update the colour and width?

I tried plt.clf() in the Selection method and it didn't remove it at all. I also tried putting plt.clf() at the end of the initial plot. This removed the plot but the new plot was still placed below the blank figure.

from tkinter import *
import tkinter as tk
import matplotlib.pyplot as plt
from shapely.geometry import LineString
from shapely.plotting import plot_line, plot_points
from matplotlib.figure import Figure
from matplotlib.backends.backend_tkagg import (FigureCanvasTkAgg,NavigationToolbar2Tk)


root =tk.Tk()
root.title("DATA")
topFrame=tk.Frame(root)
bottomFrame=tk.Frame(root)
topFrame.pack(side='top')
bottomFrame.pack(side='bottom')


#Method and call to create initial plot
def CreatePlot(lineColour,lineWidth):
width = lineWidth
colour = "#"+ lineColour
peekFigure = Figure(figsize=(6, 4), dpi=100)
fig = plt.figure (dpi = 90,clear=True)
print("fig num: ", peekFigure)
ax = fig.add_subplot (111)
sample = LineString([(1.0,1.0), (2.0,2.0)])
plot_line(sample, ax=ax, add_points=False, alpha=0.7, color = colour,linewidth = lineWidth)
axes = plt.gca()
axes.set_aspect('equal')
plt.axis('off')
canvas = FigureCanvasTkAgg(fig, master = root)
canvas.draw()
canvas.get_tk_widget().pack()

width = 5
colour = 'ff0000'
CreatePlot(colour,width)
#plt.clf()

#Method for change in radiobutton selection
def Selection():
plt.clf()
CreatePlot(cVar.get(),wVar.get())


#Create buttons and labels
buttonExit =Button (bottomFrame, text = "Exit",command = root.destroy,width = 20)
buttonExit.pack()
labelColour = tk.Label(topFrame, text=" Colour")
labelColour.grid(row=0, column=1, sticky = 'w',padx=3, pady=2)
label3 = tk.Label(topFrame, text="Line Width")
label3.grid(row = 0, column = 2,padx=3, pady=2)


#Create radio buttons for line colour
colours = [{"colour":'red',"value":'ff0000'},{"colour":'blue',"value":"0000ff"},\
{"colour": 'amber',"value":'ffa500'},{"colour":'magenta',"value":'ff00ff'}]
cVar = tk.StringVar()
rowNo=0
radC={}
for c in colours:
columnNo = 1
rowNo=rowNo+1
radC[f'{rowNo}']= tk.Radiobutton(topFrame,text=(c["colour"]),value=(c["value"]),\
variable=cVar,command = Selection)
radC[f'{rowNo}'].grid(row = rowNo, column = columnNo,sticky='w',padx=3, pady=2)
if rowNo==1:
radC[f'{rowNo}'].select()



# Create radio buttons for line widths
widths = ["5", "10", "20","30"]
wVar = tk.IntVar()
rowNo=0
WBoxList = []
radW={}
for width in widths:
columnNo = 2
rowNo=rowNo+1
radW[f'{rowNo}']= tk.Radiobutton(topFrame,text=(width),value=(width),\
variable=wVar,command = Selection)
radW[f'{rowNo}'].grid(row = rowNo, column = columnNo,sticky='w',padx=3, pady=2)
if rowNo == 1:
radW[f'{rowNo}'].select()

root.mainloop()

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