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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 _set_padding(self, attr, value):
 """Setter for the value of a padding attribute."""

        if not value:
            setattr(self, attr, "")
        else:
            value = str(value)
            if not value.isspace():
                raise ValueError("padding must be entirely whitespace")
            setattr(self, attr, value)