• Due
• What You Need to Do
• Setup On Your Machine
• Specification
• Methods
• Test Code
• Output
• Suggestions
• Testing on Your Machine
• Copy the Script to Unix
• Testing the Script on Unix (Optional)

Due

Sunday, April 5th at 11:59 PM

What You Need to Do

• Create the script hw9.py
• Make sure it obeys the rules in Rules for Homework Scripts
• Make sure the script has a hashbang line and is executable
• Move it to an an hw9 directory on pe15.cs.umb.edu

Setup On Your Machine

• Open a text editor.
  I would suggest the text editor built into the program IDLE.
• Save the file as hw9.py

Specification

• Define the class DVD that has the following attributes
  • title
  • studio
  • director
  • released
• The class must have the following methods
  • get_title
  • get_studio
  • get_director
  • get_released
  • __str__
• All the attributes in this class MUST be hidden.

Methods

__init__

• Header

  def __init__(self, title, studio, director, released):

• This method must set all attributes

get_title

• Header

  def get_title(self):

• This method returns the value of the title attribute

get_studio

• Header

  def get_studio(self):

• This method returns the value of the studio attribute

get_director

• Header

  def get_director(self):

• This method returns the value of the director attribute

get_released

• Header

  def get_released(self):

• This method returns the value of the released attribute

__str__

• Header

  def __str__(self):

• This method returns a string containing all attributes with a comma between each value

Test Code

• Your script must contain the following statements

  dvd = DVD("Forbidden Planet", "Metro-Goldwyn-Mayer", "Fred M. Wilcox", "1956")
  print(dvd.get_title())
  print(dvd.get_studio())
  print(dvd.get_director())
  print(dvd.get_released())
  print(dvd)

• They should appear at the bottom of your script

Output

• The output should look something like this

  Forbidden Planet
  Metro-Goldwyn-Mayer
  Fred M. Wilcox
  1956
  Forbidden Planet, Metro-Goldwyn-Mayer, Fred M. Wilcox, 1956

Suggestions

• Write this script in stages
• Test your script at each step
• Print the steps below
• And check them off as you finish each one

1. Make a copy of your hw8.py file in your hw9 directory.
   Change the name of this file to hw9.py
   Remove all the test code from hw9.py
   Run the script.
   You should see nothing. Fix any problem you find.
2. Change __init__ by adding the parameter released.
   Copy the first line of the test code to the bottom of your script.
   Run the script.
   You should see nothing. Fix any problem you find.
3. Change __init__ and get_title so the attribute title is hidden.
   Copy the 2nd line of the test code to the bottom of your script.
   Run the script.
   Fix any problem you find.
4. Change __init__ and get_studio so the attribute studio is hidden.
   Copy the 3rd line of the test code to the bottom of your script.
   Run the script.
   Fix any problem you find.
5. Change __init__ and get_director so the attribute director is hidden.
   Copy the 4th line of the test code to the bottom of your script.
   Run the script.
   Fix any problem you find.
6. Change __init__ so it sets the value of the attribute released.
   Create the method get_released that returns the value of this attribute.
   Copy the 5th line of the test code to the bottom of your script.
   Run the script.
   Fix any problem you find.
7. Remove the method print_dvd.
   Replace it with the method __str__ which returns a string containing the values of each of the attributes.
   Copy the last line of the test code to the bottom of your script.
   Run the script.
   Fix any problem you find.

Testing on Your Machine

• Open IDLE
• Use the Open command in IDLE to open hw9.py
• Under the Run menu, select Run Module
• Your output should look something like this

  Forbidden Planet
  Metro-Goldwyn-Mayer
  Fred M. Wilcox
  1956
  Forbidden Planet, Metro-Goldwyn-Mayer, Fred M. Wilcox, 1956

Copy the Script to Unix

• Open FileZilla and connect to pe15.cs.umb.edu
• Go to your it117 directory
• Go to your hw directory
• Right-click in the whitespace inside the hw directory
• Enter hw9 in the dialog box
• Click and drag your script from the bottom left panel to the bottom right panel
• Right-click on the file and select "Permissions" from the menu
• Enter 755 in the box provided
• This will make the script executable

Testing the Script on Unix (Optional)

• Connect to pe15.cs.umb.edu using an ssh client like putty.exe (Windows) or ssh (Mac)
• Go to the directory for this exercise

  cd  it117/hw/hw9

• Run this script

  hw9.py

• You should see something like this

  Forbidden Planet
  Metro-Goldwyn-Mayer
  Fred M. Wilcox
  1956
  Forbidden Planet, Metro-Goldwyn-Mayer, Fred M. Wilcox, 1956

Copyright © 2020 Glenn Hoffman. All rights reserved. May not be reproduced without permission.