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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 intercept(work_db):
 """Look for WorkItems in `work_db` that should not be mutated due to spor metadata. For each WorkItem, find anchors for the item's file/line/columns. If an anchor exists with metadata containing `{mutate: False}` then the WorkItem is marked as SKIPPED. """


    @lru_cache()
    def file_contents(file_path):
        "A simple cache of file contents."
        with file_path.open(mode="rt") as handle:
            return handle.readlines()

    for item in work_db.work_items:
        try:
            repo = open_repository(item.module_path)
        except ValueError:
            log.info("No spor repository for %s", item.module_path)
            continue

        for _, anchor in repo.items():
            if anchor.file_path != item.module_path.absolute():
                continue

            metadata = anchor.metadata

            lines = file_contents(item.module_path)
            if _item_in_context(
                    lines, item,
                    anchor.context) and not metadata.get("mutate", True):
                log.info(
                    "spor skipping %s %s %s %s %s %s",
                    item.job_id,
                    item.operator_name,
                    item.occurrence,
                    item.module_path,
                    item.start_pos,
                    item.end_pos,
                )

                work_db.set_result(
                    item.job_id,
                    WorkResult(
                        output=None,
                        test_outcome=None,
                        diff=None,
                        worker_outcome=WorkerOutcome.SKIPPED,
                    ),
                )