A Simple Snake Game made in Python 3

snake_game.py

# Simple Snake Game in Python 3 for Beginners
# By @TokyoEdTech

import turtle
import time
import random

delay = 0.1

# Score
score = 0
high_score = 0

# Set up the screen
wn = turtle.Screen()
wn.title("Snake Game by @TokyoEdTech")
wn.bgcolor("green")
wn.setup(width=600, height=600)
wn.tracer(0) # Turns off the screen updates

# Snake head
head = turtle.Turtle()
head.speed(0)
head.shape("square")
head.color("black")
head.penup()
head.goto(0,0)
head.direction = "stop"

# Snake food
food = turtle.Turtle()
food.speed(0)
food.shape("circle")
food.color("red")
food.penup()
food.goto(0,100)

segments = []

# Pen
pen = turtle.Turtle()
pen.speed(0)
pen.shape("square")
pen.color("white")
pen.penup()
pen.hideturtle()
pen.goto(0, 260)
pen.write("Score: 0  High Score: 0", align="center", font=("Courier", 24, "normal"))

# Functions
def go_up():
    if head.direction != "down":
        head.direction = "up"

def go_down():
    if head.direction != "up":
        head.direction = "down"

def go_left():
    if head.direction != "right":
        head.direction = "left"

def go_right():
    if head.direction != "left":
        head.direction = "right"

def move():
    if head.direction == "up":
        y = head.ycor()
        head.sety(y + 20)

    if head.direction == "down":
        y = head.ycor()
        head.sety(y - 20)

    if head.direction == "left":
        x = head.xcor()
        head.setx(x - 20)

    if head.direction == "right":
        x = head.xcor()
        head.setx(x + 20)

# Keyboard bindings
wn.listen()
wn.onkeypress(go_up, "w")
wn.onkeypress(go_down, "s")
wn.onkeypress(go_left, "a")
wn.onkeypress(go_right, "d")

# Main game loop
while True:
    wn.update()

    # Check for a collision with the border
    if head.xcor()>290 or head.xcor()<-290 or head.ycor()>290 or head.ycor()<-290:
        time.sleep(1)
        head.goto(0,0)
        head.direction = "stop"

        # Hide the segments
        for segment in segments:
            segment.goto(1000, 1000)
        
        # Clear the segments list
        segments.clear()

        # Reset the score
        score = 0

        # Reset the delay
        delay = 0.1

        pen.clear()
        pen.write("Score: {}  High Score: {}".format(score, high_score), align="center", font=("Courier", 24, "normal")) 


    # Check for a collision with the food
    if head.distance(food) < 20:
        # Move the food to a random spot
        x = random.randint(-290, 290)
        y = random.randint(-290, 290)
        food.goto(x,y)

        # Add a segment
        new_segment = turtle.Turtle()
        new_segment.speed(0)
        new_segment.shape("square")
        new_segment.color("grey")
        new_segment.penup()
        segments.append(new_segment)

        # Shorten the delay
        delay -= 0.001

        # Increase the score
        score += 10

        if score > high_score:
            high_score = score
        
        pen.clear()
        pen.write("Score: {}  High Score: {}".format(score, high_score), align="center", font=("Courier", 24, "normal")) 

    # Move the end segments first in reverse order
    for index in range(len(segments)-1, 0, -1):
        x = segments[index-1].xcor()
        y = segments[index-1].ycor()
        segments[index].goto(x, y)

    # Move segment 0 to where the head is
    if len(segments) > 0:
        x = head.xcor()
        y = head.ycor()
        segments[0].goto(x,y)

    move()    

    # Check for head collision with the body segments
    for segment in segments:
        if segment.distance(head) < 20:
            time.sleep(1)
            head.goto(0,0)
            head.direction = "stop"
        
            # Hide the segments
            for segment in segments:
                segment.goto(1000, 1000)
        
            # Clear the segments list
            segments.clear()

            # Reset the score
            score = 0

            # Reset the delay
            delay = 0.1
        
            # Update the score display
            pen.clear()
            pen.write("Score: {}  High Score: {}".format(score, high_score), align="center", font=("Courier", 24, "normal"))

    time.sleep(delay)

wn.mainloop()

arrow keys are not working in ubuntu how to play the game

Change each of the letters for up, down, etc in the "onkeypress" statements to correspond to the literal words "Up" "Down" "Left" and "Right" in place of the 'wsad' options, and you'll get keyboard arrow functionality.