Check that comparisons are overlapping [comparison-overlap]

If you use —strict-equality, mypy will generate an error if itthinks that a comparison operation is always true or false. These areoften bugs. Sometimes mypy is too picky and the comparison canactually be useful. Instead of disabling strict equality checkingeverywhere, you can use # type: ignore[comparison-overlap] toignore the issue on a particular line only.

Example:

# mypy: strict-equality
 
def is_magic(x: bytes) -> bool:
    # Error: Non-overlapping equality check (left operand type: "bytes",
    #        right operand type: "str")  [comparison-overlap]
    return x == 'magic'

We can fix the error by changing the string literal to a bytesliteral:

# mypy: strict-equality
 
def is_magic(x: bytes) -> bool:
    return x == b'magic'  # OK