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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 to_ising(self):
 """Converts a binary quadratic model to Ising format. If the binary quadratic model's vartype is not :class:`.Vartype.SPIN`, values are converted. Returns: tuple: 3-tuple of form (`linear`, `quadratic`, `offset`), where `linear` is a dict of linear biases, `quadratic` is a dict of quadratic biases, and `offset` is a number that represents the constant offset of the binary quadratic model. Examples: This example converts a binary quadratic model to an Ising problem. ({0: 1, 1: -1, 2: 0.5}, {(0, 1):
 0.5, (1, 2):
 1.5}, 1.4) """

        # cast to a dict
        return dict(self.spin.linear), dict(self.spin.quadratic), self.spin.offset