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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 _check_all_metadata_found(metadata, items):
 """Print warning if samples in CSV file are missing in folder"""

    for name in metadata:
        seen = False
        for sample in items:
            check_file = sample["files"][0] if sample.get("files") else sample["vrn_file"]
            if isinstance(name, (tuple, list)):
                if check_file.find(name[0]) > -1:
                    seen = True
            elif check_file.find(name) > -1:
                seen = True
            elif "*" in name and fnmatch.fnmatch(check_file, "*/%s" % name):
                seen = True
        if not seen:
            print("WARNING: sample not found %s" % str(name))