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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 indent(self, value):
 """Validate and set the indent width."""

        # Explicit indent setting
        if isinstance(value, str):
            if value.isspace() or len(value) == 0:
                self._indent = value
            else:
                raise ValueError('String indentation can only contain '
                                 'whitespace.')

        # Set indent width
        elif isinstance(value, int):
            if value >= 0:
                self._indent = value * ' '
            else:
                raise ValueError('Indentation spacing must be nonnegative.')

        else:
            raise TypeError('Indentation must be specified by string or space '
                            'width.')