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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 useful_mimetype(text):
 """Check to see if the given mime type is a MIME type which is useful in terms of how to treat this file. """

    if text is None:
        return False
    mimetype = normalize_mimetype(text)
    return mimetype not in [DEFAULT, PLAIN, None]