Extracting SLA Data from Jira API

I’m working on utilizing the Jira API to extract data regarding created tickets into a different database. The tickets are configured to comply with ITIL standards, which include ‘Time to First Response’ (TTFR) and ‘Time to Resolution’ (TTR). I receive these values in JSON format, displayed as hexadecimal references, for example:

<custom_field_10110>com.atlassian.servicedesk.internal.sla.model.SLAValue@12345678</custom_field_10110>
<custom_field_10111>com.atlassian.servicedesk.internal.sla.model.SLAValue@87654321</custom_field_10111>

However, I’m unsure how to convert these hex values to retrieve the actual TTFR and TTR values that are visible in the ticket.