There is a sample Python program that uses Python's tkinter and maplotlib packages to illustrate the workings of the model$-$view$-$controller pattern.$$See if you can get this program running on your computer.$$Provide a short paragraph $($in comments in the source code$)$ explaining the relationship between each of the three pattern components.

import tkinter as Tk

from matplotlib.figure import Figure

from matplotlib.backends.backend$\_$tkagg import FigureCanvasTkAgg

import numpy as np

$$

$$

class Model$()$:

$$

$$ def $\_\_$init$\_\_($self$)$:

$$ self.xpoint $=200$

$$ self.ypoint $=200$

$$ self.res $=$ None

$$

$$ def calculate$($self$)$:

$$ x$,$ y $=$ np$.$meshgrid$($np$.$linspace$(-5,5,$ self.xpoint$),$

$$np$.$linspace$(-5,5,$ self.ypoint$))$

$$ z $=$ np$.$cos$($x$**2*$y$**3)$

$$ self.res $=\{"$x$"$: x$,"$y$"$: y$,"$z$"$: z$\}$

$$

$$

class View$()$:

$$ def $\_\_$init$\_\_($self$,$ master$)$:

$$ self.frame $=$ Tk$.$Frame$($master$)$

$$ self.fig $=$ Figure$($figsize$=(7\mathrm{.}5,4),$ dpi$=80)$

$$ self.ax$0=$ self.fig.add$\_$axes$($

$(0\mathrm{.}05,\mathrm{.}05,\mathrm{.}90,\mathrm{.}90),$ facecolor$=(\mathrm{.}75,\mathrm{.}75,\mathrm{.}75),$ frameon$=$False$)$

$$ self.frame.pack$($side$=$Tk$.$LEFT, fill$=$Tk$.$BOTH, expand$=1)$

$$ self.sidepanel $=$ SidePanel$($master$)$

$$ self.canvas $=$ FigureCanvasTkAgg$($self$.$fig, master$=$self.frame$)$

$$ self.canvas.get$\_$tk$\_$widget$().$pack$($side$=$Tk$.$TOP, fill$=$Tk$.$BOTH, expand$=1)$

$$ self.canvas.draw$()$

$$

$$

class SidePanel$()$:

$$ def $\_\_$init$\_\_($self$,$ root$)$:

$$ self.frame$2=$ Tk$.$Frame$($root$)$

$$ self.frame$2.$pack$($side$=$Tk$.$LEFT, fill$=$Tk$.$BOTH, expand$=1)$

$$ self.plotBut $=$ Tk$.$Button$($self$.$frame$2,$ text$=$"Plot $")$

$$ self.plotBut.pack$($side$=$"top", fill$=$Tk$.$BOTH$)$

$$ self.clearButton $=$ Tk$.$Button$($self$.$frame$2,$ text$=$"Clear"$)$

$$ self.clearButton.pack$($side$=$"top", fill$=$Tk$.$BOTH$)$

$$

$$

class Controller$()$:

$$ def $\_\_$init$\_\_($self$)$:

$$ self.root $=$ Tk$.$Tk$()$

$$ self.model $=$ Model$()$

$$ self.view $=$ View$($self$.$root$)$

$$ self.view.sidepanel.plotBut.bind$("",$ self.my$\_$plot$)$

$$ self.view.sidepanel.clearButton.bind$("",$ self.clear$)$

$$

$$ def run$($self$)$:

$$ self.root.title$("$Tkinter MVC example"$)$

$$ self.root.deiconify$()$

$$ self.root.mainloop$()$

$$

$$ def clear$($self$,$ event$)$:

$$ self.view.ax$0.$clear$()$

$$ self.view.fig.canvas.draw$()$

$$

$$ def my$\_$plot$($self$,$ event$)$:

$$ self.model.calculate$()$

$$ self.view.ax$0.$clear$()$

$$ self.view.ax$0.$contourf$($

$$ self.model.res$["$x$"],$ self.model.res$["$y$"],$ self.model.res$["$z$"])$

$$ self.view.fig.canvas.draw$()$

$$

$$

if $\_\_$name$\_\_==\text{'}\_\_$main$\_\_\text{'}$:

$$ c $=$ Controller$()$

$$ c$.$run$()$