Python Interpreter (Shell)

In the previous chapter, we learned how to install python on different OS machines. In case if you didn’t install python, check the python installation article.

 

When you install python on your machine, it will install the python interpreter or python shell, IDLE, and other required components to implement the applications using the python programming language.

 

As python is an interpreted programming language, you can execute the Python programs in two ways, i.e., directly write and run the code in python interpreter command-line interface or write code in the source (.py) file and execute the file from python interpreter. Now, we will learn how to write and run python programs using both methods.

Using Python Interpreter

To open the python interpreter command-line interface, search for python in the start menu and click on the Python app like as shown below.

 

Open python interpreter or shell by searching

 

After opening the python interpreter command-line interface, you will see the greater than (>>>) symbols like as shown below, that means you are ready to start typing your code.

 

python interpreter command line interface

 

After opening your python interpreter, type print("Hello World") command in the console and click on the Enter button to print the Hello World text like as shown below.

 

Python Shell or Interpreter Hello World Program Example

 

If you observe the above result, we tried to print a message in the python shell by typing the message print("Hello World"). After we type a message and click on Enter, immediately it returned the string whatever we mentioned in a terminal.

Using Command Prompt

Instead of a Python shell or interpreter, you can also execute the python code through a command prompt for that open the command prompt, type python, and press the Enter button like as shown below.

 

Execute python in command prompt

 

Whenever the python started, you will see the greater than (>>>) symbol that means you are ready to start typing your code. If you want, you can also perform different operations like as shown below.

 

Python interpreter command prompt examples

 

If you observe the above results, the python shell or interpreter executes a single statement and returns the results. If you want to execute the multiple code lines, you need to create python files to execute the code using a python interpreter.

Using Files in Python

As python is an interpreted programming language, you can write the python code using different text editors and save those files with .py extension. After that, you can execute that python (.py) files either using direct python shell or by enabling the python in command prompt.

 

You can open any text editor like Notepad, create a file called Helloworld.py and write the code like as shown below.

 

print("Welcome to Tutlane.com")
print("Learn Python with Examples")

Now, the python files can execute by using command prompt (cmd) for that open command prompt and navigate to the folder that contains the Helloworld.py file like as shown below.

 

Python shell navigate to folder to execute hello world script

 

Generally, the python files can execute by entering a command like python <Your_File_Name>, so enter a command python Helloworld.py and hit the enter button.

 

Python Shell or Interpreter Execute Hello World Program Script

 

Instead of the Python shell or command prompt, you can also execute the code using Python IDLE. In the next chapter, we will learn more about Python IDLE to execute the Python programs.

Exit Python Interpreter Prompt

After completing python code execution, if you want to exit or quit the python interpreter or command prompt, enter command exit() and press Enter to exit the python interpreter prompt.