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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 get_energy(self, circuit, sampler):
 """Calculate energy from circuit and sampler."""

        val = 0.0
        for meas in self.hamiltonian:
            c = circuit.copy()
            for op in meas.ops:
                if op.op == "X":
                    c.h[op.n]
                elif op.op == "Y":
                    c.rx(-np.pi / 2)[op.n]
            measured = sampler(c, meas.n_iter())
            for bits, prob in measured.items():
                if sum(bits) % 2:
                    val -= prob * meas.coeff
                else:
                    val += prob * meas.coeff
        return val.real