WhoisXML API offers, via API calls, a lot of information on domains or IP addresses that is very useful for a number of applications, including cybersecurity investigations, domain appraisal or system administration. Imagine that one is given a long list of domain names, and one is interested in each domain's details, e.g., WHOIS or website categories, etc. In each API call, a single domain name is sent, and its data is returned in JSON format. (Some of the APIs of WhoisXML API offer bulk lookups, too, but we will not deal with this possibility here.) To get an overview of the data, analysts often prefer to have everything in a single csv file; one line for each domain. This can be opened by popular office spreadsheets like Excel or LibreOffice Calc, or sent to other kinds of processing.