Python syntax example code analysis

Execute Python syntax

As we learned in the previous section, you can write the syntax to execute Python directly on 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 from the command line:

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

Python Indentation

Indentation refers to the spaces at the beginning of lines of code.

In other programming languages, code indentation is only for readability, but indentation in Python is very important.

Python uses indentation to indicate blocks of code.

Example

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

Running Example

##If indentation is omitted, Python will error:

Example

Syntax error:

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

Running Example

The number of spaces depends on the programmer, but At least one is required.

Example

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

Running Example

You must use the same number of spaces in the same code block, Otherwise Python will error:

Example

Syntax error:

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

Run Example

Python variables

In Python, a variable is created when a value is assigned to it:

Example

Variables in Python:

x = 5
y = "Hello, World!"

Run Example

Python No command to declare variables

In the Python Variables chapter we learn more about variables.

Comments

Python has the function of commenting the code in the document.

Comments start with # and Python renders the rest as a comment:

Example

Comments in Python:

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

Running instance

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