Python Coding Standards: PEP 8

Syntax and Naming Conventions

• ALWAYS adhere to the PEP 8 guideline for maximum line length of 79 characters for code and 72 for comments.
• MANDATORY use of snake_case for function and variable names.
• MUST use CapWords convention for class names.

Indentation and Whitespace

• REQUIRED to use 4 spaces per indentation level. NEVER use tabs for indentation.
• ALWAYS surround these binary operators with a single space on either side: assignment (=), augmented assignment (+=, -=, etc.), comparisons (==, <, >, !=, <>, <=, >=, in, not in, is, is not), Booleans (and, or, not).
• NEVER add extra spaces around function calls, brackets, or keyword arguments.
• MANDATORY single new line at the end of each file.

Comments

• REQUIRED to keep comments up-to-date with code changes.
• MUST write comments as complete sentences.
• Inline comments SHOULD be used sparingly.
• ALWAYS place inline comments on the line immediately above the code line it refers to and should be indented to the same level.

Docstrings

• MANDATORY to include docstrings for public modules, functions, classes, and methods.
• REQUIRED docstrings should follow the "numpydoc" docstring guide.

Imports

• MUST place all imports at the top of the file.
• ALWAYS use absolute imports over relative imports.
• Imports SHOULD be grouped in the following order:
  1. Standard library imports.
  2. Related third party imports.
  3. Local application/library specific imports.
• MANDATORY to put a blank line between each group of imports.

Exception Handling

• ALWAYS use explicit exception handling rather than generic exceptions, except for the final block.
• SHOULD minimize the amount of code in a try block.

Programming Recommendations

• NEVER use lambdas which are complex; instead, define a function.
• ALWAYS use list comprehensions and generator expressions for simple tasks, preferring these over manual "for" loops and map function calls.
• Comparisons to singletons like None SHOULD always be done with is or is not, never the equality operators.

Testing and Debugging

• REQUIRED to write tests for modules and functions.
• Debug print statements SHOULD never appear in the final code.

Code Layout

• MANDATORY to separate top-level function and class definitions with two blank lines.
• Method definitions inside a class SHOULD be separated by a single blank line.
• NEVER use multiple statements on a single line (e.g., a = 1; b = 2).