code: def process_fixed_issues(self, volumes, existing_issues):
          
          fixed_issues = []
          for issue_id, issue in list(existing_issues.items()):
              if issue_id not in volumes:
                  fixed_issues.append(issue)
  
          return fixed_issues
docs: Provided a list of volumes and existing issues, returns a list of fixed issues to be deleted
  
          Args:
              volumes (`dict`): A dictionary keyed on the issue id, with the :obj:`Volume` object as the value
              existing_issues (`dict`): A dictionary keyed on the issue id, with the :obj:`EBSVolumeAuditIssue` object as
              the value
  
          Returns:
              :obj:`list` of :obj:`EBSVolumeAuditIssue`