As a librarian, I want to be able to display the holdings and item copy number fields to my library patron so they know the exact copy to request / to check out / or ask the librarian. 

Requirements

• Add to the response the field holdingsCopyNumber. Populated with the holdings copy number field. If no holdings copy number value is entered then do not return it in the response. 

• Add to the response the field itemCopyNumber. Populated with the item copy number field. If no item copy number value is entered then do not return it in the response. 

Example of API response that returns holdings and item copy numbers because both have values

Example of API response that only returns holdingsCopyNumber because itemCopyNumber has no value

Example of API response that only returns itemCopyNumber because holdingsCopyNumber has no value

Example of API response when both holdingsCopyNumber and itemCopyNumber has no values