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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def process_fixed_issues(self, volumes, existing_issues):
 """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` """

        fixed_issues = []
        for issue_id, issue in list(existing_issues.items()):
            if issue_id not in volumes:
                fixed_issues.append(issue)

        return fixed_issues