Octal literals starting with 0 are easily misread as a decimal, particularly by those programmers who do not have a C or Java background.

The new literal syntax for non-decimal numbers is more distinct and is thus less likely to be misunderstood.

Use the 0oXXX form instead of the 0XXX form. Alternatively use binary or hexadecimal format if that would be clearer.

  • Python Language Reference: Integer Literals.
  • Python PEP 3127: Integer Literal Support and Syntax.
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