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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 show_closed_prs(self):
 """Log only closed PRs."""

        all_prs = self.collect_prs_info()
        for pr_info in all_prs.get('closed', []):
            logger.info(
                '{url} in state {state} ({merged})'.format(**pr_info)
            )