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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 t(self, value):
 """Set new branch lengths, update likelihood and derivatives."""

        assert (isinstance(value, scipy.ndarray) and (value.dtype ==
                'float') and (value.shape == self.t.shape))
        if (self._t != value).any():
            self._t = value.copy()
            self._updateInternals()