Python Syntax

Execute Python Syntax

As we learned in the previous page, Python syntax can be executed by writing directly in the Command Line:

>>> print("Hello, World!")
Hello, World!

Or by creating a python file on the server, using the .py file extension, and running it in the Command Line:

C:\Users\Your Name>python myfile.py

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Python Indentations

Where in other programming languages the indentation in code is for readability only, in Python the indentation is very important.

Python uses indentation to indicate a block of code.

Example

if 5 > 2:
  print("Five is greater than two!")

Show Python »
C:\Users\My Name>python demo_indentation.py
Five is greater than two!                  
                                           
                                           
                                           

Python will give you an error if you skip the indentation:

Example

if 5 > 2:
print("Five is greater than two!")

Show Python »
C:\Users\My Name>python demo_indentation_test.py
  File "demo_indentation_test.py", line 2       
    print("Five is greater than two!")          
        ^                                       
IndentationError: expected an indented block    
                                                
                                                

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Comments

Python has commenting capability for the purpose of in-code documentation.

Comments start with a #, and Python will render the rest of the line as a comment:

Example

Comments in Python:

#This is a comment.print("Hello, World!")

Show Python »
C:\Users\My Name>python demo_comment.py
Hello, World!                          
                                       
                                       

Docstrings

Python also has extended documentation capability, called docstrings.

Docstrings can be one line, or multiline.

Python uses triple quotes at the beginning and end of the docstring:

Example

Docstrings are also comments:

"""This is a 
multiline docstring."""
print("Hello, World!")

Show Python »
C:\Users\My Name>python demo_docstring.py
Hello, World!