## Summary We have this pattern in a bunch of places, where we find the _only_ binding to a name (and return `None`) if it's bound multiple times. This PR DRYs it up into a method on `SemanticModel`.
## Summary We have this pattern in a bunch of places, where we find the _only_ binding to a name (and return `None`) if it's bound multiple times. This PR DRYs it up into a method on `SemanticModel`.