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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 validate_confusables(value):
 """ Validator which disallows 'dangerous' usernames likely to represent homograph attacks. A username is 'dangerous' if it is mixed-script (as defined by Unicode 'Script' property) and contains one or more characters appearing in the Unicode Visually Confusable Characters file. """

    if not isinstance(value, six.text_type):
        return
    if confusables.is_dangerous(value):
        raise ValidationError(CONFUSABLE, code='invalid')