matplotlib viewer not displaying when I run code

I am very new to Python and am trying to work my way through the introductory book "Python Crash Course". I am working on one of the projects which is to model a random walk in matplotlib. However, I cannot get the viewer to display when I run the file "Data_Vis.py". This file imports the class RandomWalk from the file "random_walk.py". I am able to run both files with zero errors, but as I said I would expect to see a graphing generated. Thanks in advance for any help!!!

"Data_Vis.py"

import matplotlib.pyplot as plt
from random_walk import RandomWalk

rw = RandomWalk()
rw.fill_walk()

plt.scatter(rw.x_values,rw.y_values,s=15)
plt.show()

---

"random_walk.py"

from random import choice

class RandomWalk():

    def __init__(self,num_points=100):
        self.num_points = num_points

        self.x_values = [0]
        self.y_values = [0]

    def fill_walk(self):


        while len(self.x_values) < self.num_points:
            x_direction = choice([-1,1])
            x_distance = choice([0,1,2,3,4])
            x_step = x_direction * x_distance

            y_direction = choice([-1,1])
            y_distance = choice([0,1,2,3,4])
            y_step = y_direction * y_distance

            if x_step == 0 and y_step == 0:
                continue

                next_x = self.x_values[-1] + x_step
                next_y = self.y_values[-1] + y_step

                self.x_values.append(next_x)
                self.y_values.append(next_y)