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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 _convert_to_boolean(self, value):
 """Return a boolean value translating from other types if necessary. """

        if value.lower() not in self.BOOLEAN_STATES:
            raise ValueError('Not a boolean: %s' % value)
        return self.BOOLEAN_STATES[value.lower()]