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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 is_ner(tag):
 """ Check the 10th column of the first token to determine if the file contains NER tags """

    tag_match = re.match("([A-Z_]+)-([A-Z_]+)", tag)
    if tag_match:
        return True
    elif tag == "O":
        return True
    else:
        return False