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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_time_evolution(self):
 """Get the function to append the time evolution of this term. Returns: function(circuit: Circuit, t: float):
 Add gates for time evolution to `circuit` with time `t` """

        term = self.simplify()
        coeff = term.coeff
        if coeff.imag:
            raise ValueError("Not a real coefficient.")
        ops = term.ops
        def append_to_circuit(circuit, t):
            if not ops:
                return
            for op in ops:
                n = op.n
                if op.op == "X":
                    circuit.h[n]
                elif op.op == "Y":
                    circuit.rx(-half_pi)[n]
            for i in range(1, len(ops)):
                circuit.cx[ops[i-1].n, ops[i].n]
            circuit.rz(-2 * coeff * t)[ops[-1].n]
            for i in range(len(ops)-1, 0, -1):
                circuit.cx[ops[i-1].n, ops[i].n]
            for op in ops:
                n = op.n
                if op.op == "X":
                    circuit.h[n]
                elif op.op == "Y":
                    circuit.rx(half_pi)[n]
        return append_to_circuit