## Summary
Related to #15848, this PR adds the imports explicitly as we'll now flag
these symbols as undefined.
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Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>
Just like in #15045 for unary expressions: In binary expressions, we
were only looking for dunder expressions for `Type::Instance` types. We
had some special cases for coercing the various `Literal` types into
their corresponding `Instance` types before doing the lookup. But we can
side-step all of that by using the existing `Type::to_meta_type` and
`Type::to_instance` methods.