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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_params(self, x):
 """set the value of the parameters."""

        assert x.size == self.num_params
        self.varianceU = x[0]
        self.varianceY = x[1]
        self.lengthscaleU = x[2]
        self.lengthscaleY = x[3]