Getting Started with Python (2024)

Installation of Python

• Download the current production version of Python (2.7.1) from the Python Download site.
• Double click on the icon of the file that you just downloaded.
• Accept the default options given to you until you get to the Finish button. Your installation is complete.

Setting up the Environment

• Starting at My Computer go to the following directory C:\Python27. In that folder you should see all the Python files.
• Copy that address starting with C: and ending with 27and close that window.
• Click on Start. Right Click on My Computer.
• Click on Properties. Click on Advanced System Settings orAdvanced.
• Click on Environment Variables.
• Under System Variables search for the variable Path.
• Select Path by clicking on it. Click on Edit.
• Scroll all the way to the right of the field called Variablevalue using the right arrow.
• Add a semi-colon (;) to the end and paste the path (to the Python folder) that you previously copied. Click OK.

Writing Your First Python Program

• Create a folder called PythonPrograms on your C:\ drive. You will be storing all your Python programs in this folder.
• Go to Start and either type Run in the Start Searchbox at the bootom or click on Run.
• Type in notepad in the field called Open.
• In Notepad type in the following program exactly as written:

# File: Hello.pyprint "Hello World!"

• Go to File and click on Save as.
• In the field Save in browse for the C: drive and thenselect the folder PythonPrograms.
• For the field File name remove everything that is thereand type in Hello.py.
• In the field Save as type select All Files
• Click on Save. You have just created your first Python program.

Running Your First Program

• Go to Start and click on Run.
• Type cmd in the Open field and click OK.
• A dark window will appear. Type cd C:\ and hit the key Enter.
• If you type dir you will get a listing of all folders inyour C: drive. You should see the folder PythonPrograms that youcreated.
• Type cd PythonPrograms and hit Enter. It should take you to thePythonPrograms folder.
• Type dir and you should see the file Hello.py.
• To run the program, type python Hello.py and hit Enter.
• You should see the line Hello World!
• Congratulations, you have run your first Python program.

Python comes bundled with Mac OS X. But the version that you have is quite likely an older version. Download the latestbinary version of Python that runs on both Power PC and Intel systems andinstall it on your system.

Writing Your First Python Program

• Click on File and then New Finder Window.
• Click on Documents.
• Click on File and then New Folder.
• Call the folder PythonPrograms. You will be storing all class relatedprograms there.
• Click on Applications and then TextEdit.
• Click on TextEdit on the menu bar and select Preferences.
• Select Plain Text.
• In the empty TextEdit window type in the following program, exactlyas given:

# File: Hello.pyprint "Hello World!"

• From the File menu in TextEdit click on Save As.
• In the field Save As: type Hello.py.
• Select Documents and the file folder PythonPrograms.
• Click Save.

Running Your First Program

• Select Applications, then Utilities and Terminal.
• In your Terminal window type ls and Return. It should give a listing of all the top level folders. You should see the Documents folder.
• Type cd Documents and hit Return.
• Type ls and hit Return and you should see the folder PythonPrograms.
• Type cd PythonPrograms and hit Return.
• Type ls and hit return and you should see the file Hello.py.
• To run the program, type python Hello.py and hit Return.
• You should see the line Hello World!
• Congratulations, you have run your first Python program.

Starting IDLE on Mac

• In a Terminal window, type python. This will startthe Python shell. The prompt for that is >>>
• At the Python shell prompt type import idlelib.idle
• This will start the IDLE IDE

Using IDLE on either Windows or Mac

• Start IDLE
• Go to File menu and click on New Window
• Type your program in
• Go to File menu and click on Save. Type in filename.py This will save it as a plain text file, which can be opened in in any editor you choose (like Notepad or TextEdit).
• To run your program go to Run and click Run Module