Python · Theory

Python Syntax

Theory

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Python Syntax

Syntax is the rulebook. If you break it, Python refuses to run. Indentation defines blocks — usually 4 spaces. if, for, def, class lines end with a colon, then the body sits under them. No semicolon needed at the end of a normal line.

Python is case sensitive: Name and name are different. Mix tabs and spaces and you get IndentationError. # starts a comment. Freshers coming from Java keep adding braces; Python does not want them for blocks.

Exam line — indentation is not style. It is syntax. Say that, then show one if with a colon and two indented prints.

Python Syntax — output — Adult. The print sits inside if because it is indented.

Diagram

if marks >= 40:
      print("Pass")   ← indent = block
  else:
      print("Fail")

Exam tip

IndentationError — explain why it is syntax.

Example

# Syntax
age = 18
if age >= 18:
    print("Adult")
# print("Adult")  # wrong indent would crash

Python Syntax — output: Adult. The print sits inside if because it is indented.

Short notes

DefIndentation defines blocks.
RuleColon then indent.
RememberCase sensitive.
TrapTabs mixed with spaces.

Python · Theory

Python Syntax

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Theory

8/268

Python Syntax

Exam line — indentation is not style. It is syntax. Say that, then show one if with a colon and two indented prints.

Python Syntax — output — Adult. The print sits inside if because it is indented.

Diagram

if marks >= 40:
      print("Pass")   ← indent = block
  else:
      print("Fail")

Exam tip

IndentationError — explain why it is syntax.

Example

# Syntax
age = 18
if age >= 18:
    print("Adult")
# print("Adult")  # wrong indent would crash

Python Syntax — output: Adult. The print sits inside if because it is indented.

Short notes

DefIndentation defines blocks.
RuleColon then indent.
RememberCase sensitive.
TrapTabs mixed with spaces.

Python Syntax

Example

Short notes

Questions

Python Syntax

Example

Short notes

Questions