```ruby
class ScsbLookup
  include Scsb

  def find_by_id(id)
    response = items_by_id(id)
    response.map { |r| [r['itemBarcode'], r] }.to_h
  rescue Faraday::ConnectionFailed => connection_failed
    logger.warn("No barcodes could be retrieved for the item: #{id}")
    {}
  end

  def find_by_barcodes(barcodes)
    response = items_by_barcode(barcodes)
    response.map { |r| [r['itemBarcode'], r] }.to_h
  rescue Faraday::ConnectionFailed => connection_failed
    logger.warn("No items could be retrieved for the barcodes: #{barcodes.join(',')}")
    {}
  end
end
```

Remove useless assignment for rubocop
user
```ruby
class ScsbLookup
  include Scsb

  def find_by_id(id)
    response = items_by_id(id)
    response.map { |r| [r['itemBarcode'], r] }.to_h
  rescue Faraday::ConnectionFailed
    logger.warn("No barcodes could be retrieved for the item: #{id}")
    {}
  end

  def find_by_barcodes(barcodes)
    response = items_by_barcode(barcodes)
    response.map { |r| [r['itemBarcode'], r] }.to_h
  rescue Faraday::ConnectionFailed
    logger.warn("No items could be retrieved for the barcodes: #{barcodes.join(',')}")
    {}
  end
end
```
assistant