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Simplify Boolean Expressions Using `isinstance` and `issubclass`


ImportanceReview GuidanceRequires Scanning Tool
LowMerge Without ReviewNo

Many developers are not necessarily aware that the isinstance and issubclass builtin methods can accept a tuple of classes to match. This means that there is a lot of code that uses boolean expressions such as isinstance(x, str) or isinstance(x, bytes) instead of the simpler expression isinstance(x, (str, bytes)).

This codemod simplifies the boolean expressions where possible which leads to cleaner and more concise code.

The changes from this codemod look like this:

  x = 'foo'
- if isinstance(x, str) or isinstance(x, bytes):
+ if isinstance(x, (str, bytes)):

If you have feedback on this codemod, please let us know!


Why is this codemod marked as Merge Without Review?

Simplifying expressions involving isinstance or issubclass calls is safe.

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