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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(self, value):
 """ Only allow ASCII and None values. Check against US-ASCII, a.k.a. 7-bit ASCII, a.k.a. ISO646-US, a.k.a. the Basic Latin block of the Unicode character set. Source: https://github.com/apache/cassandra/blob /3dcbe90e02440e6ee534f643c7603d50ca08482b/src/java/org/apache/cassandra /serializers/AsciiSerializer.java#L29 """

        value = super(Ascii, self).validate(value)
        if value:
            charset = value if isinstance(
                value, (bytearray, )) else map(ord, value)
            if not set(range(128)).issuperset(charset):
                raise ValidationError(
                    '{!r} is not an ASCII string.'.format(value))
        return value