Code Indentation

• Python uses indentation levels rather than the braces used by other languages to demarcate code blocks.
• By convention, contemporary Python code is indented by four spaces for each level.
• All code blocks in Python code are easily identifiable and everyone writes them the same way.

Whitespace is significant

In Python whitespace is significant. Block starts with significant white space, The block ends when the indentation becomes smaller (less).

print("Code Indentation Demo")
if True:
    print("Begin of Block")
print("Not part of if block") # Less indentation , not a part of block

Even below code style is correct but not recommended. Having four spaces is preferable

print("Code Indentation Demo")
if True:
 print("Begin of Block")
print("Not part of if block") # Less indentation , not a part of block

Significant Whitespace Rules

• Prefer four spaces
• Never mix spaces and tabs
• Be consistent on consecutive lines
• Only deviate to improve readability

PEP 8(Python Enhancement Proposals)

PEP 8 - Style Guide for Python Code.

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