How to Properly Equate Booleans in Python for SQLAlchemy Queries?

Equating Booleans in Python: Addressing Flake8 Warnings

In Python, comparing booleans with "==" can trigger flake8 warnings when used in filter clauses for SQLAlchemy queries. Specifically, the warning "E712: Comparison to False should be 'if cond is False:' or 'if not cond:'" is raised.

To resolve this, there are three possible approaches:

• Suppress the Warning with # noqa: Add a # noqa comment to the offending line to suppress the flake8 warning. This is the simplest solution, but it doesn't address the underlying issue.
• Use SQL "IS" Expression: SQLAlchemy filters support the SQL "IS" expression. Instead of "TestCase.obsoleted == False", you can use "TestCase.obsoleted.is_(False)". This will work across different database dialects.
• Utilize sqlalchemy.sql.expression.false: Import "sqlalchemy.sql.expression" and use "TestCase.obsoleted == sqlalchemy.sql.expression.false()". This method returns the correct value for the specific session SQL dialect. There is also a matching "sqlalchemy.expression.true()".

It's important to note that while comparing booleans with "==" in filter clauses is technically correct in SQLAlchemy, it can lead to confusion in other contexts. Therefore, it's best practice to avoid using "==" for boolean comparisons in non-filter clauses to prevent potential issues.

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