```"""
Simple graphics demo

Sample Python/Pygame Programs
Simpson College Computer Science
http://simpson.edu/computer-science/

"""

# Import a library of functions called 'pygame'
import pygame

# Initialize the game engine
pygame.init()

# Define some colors
BLACK = (0, 0, 0)
WHITE = (255, 255, 255)
BLUE = (0, 0, 255)
GREEN = (0, 255, 0)
RED = (255, 0, 0)

PI = 3.141592653

# Set the height and width of the screen
size = (400, 500)
screen = pygame.display.set_mode(size)

pygame.display.set_caption("Professor Craven's Cool Game")

# Loop until the user clicks the close button.
done = False
clock = pygame.time.Clock()

# Loop as long as done == False
while not done:

for event in pygame.event.get():  # User did something
if event.type == pygame.QUIT:  # If user clicked close
done = True  # Flag that we are done so we exit this loop

# All drawing code happens after the for loop and but
# inside the main while not done loop.

# Clear the screen and set the screen background
screen.fill(WHITE)

# Draw on the screen a line from (0,0) to (100,100)
# 5 pixels wide.
pygame.draw.line(screen, GREEN, [0, 0], [100, 100], 5)

# Draw on the screen several lines from (0,10) to (100,110)
# 5 pixels wide using a loop
for y_offset in range(0, 100, 10):
pygame.draw.line(screen, RED, [0, 10 + y_offset], [100, 110 + y_offset], 5)

# Draw a rectangle
pygame.draw.rect(screen, BLACK, [20, 20, 250, 100], 2)

# Draw an ellipse, using a rectangle as the outside boundaries
pygame.draw.ellipse(screen, BLACK, [20, 20, 250, 100], 2)

# Draw an arc as part of an ellipse.
# Use radians to determine what angle to draw.
pygame.draw.arc(screen, BLACK, [20, 220, 250, 200], 0, PI / 2, 2)
pygame.draw.arc(screen, GREEN, [20, 220, 250, 200], PI / 2, PI, 2)
pygame.draw.arc(screen, BLUE, [20, 220, 250, 200], PI, 3 * PI / 2, 2)
pygame.draw.arc(screen, RED, [20, 220, 250, 200], 3 * PI / 2, 2 * PI, 2)

# This draws a triangle using the polygon command
pygame.draw.polygon(screen, BLACK, [[100, 100], [0, 200], [200, 200]], 5)

# Select the font to use, size, bold, italics
font = pygame.font.SysFont('Calibri', 25, True, False)

# Render the text. "True" means anti-aliased text.
# Black is the color. This creates an image of the
# letters, but does not put it on the screen
text = font.render("My text", True, BLACK)

# Put the image of the text on the screen at 250x250
screen.blit(text, [250, 250])

# Go ahead and update the screen with what we've drawn.
# This MUST happen after all the other drawing commands.
pygame.display.flip()

# This limits the while loop to a max of 60 times per second.
# Leave this out and we will use all CPU we can.
clock.tick(60)

# Be IDLE friendly
pygame.quit()

```
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