虽然我导入了plot_histogram，但我没有得到预期的输出。这是我的代码：
a = QuantumCircuit(1)
a.z(0)
a.x(0)
a.h(0)
a.sdg(0)
a.t(0)
backend = Aer.get_backend('qasm_simulator')
result = execute(a, backend).result()
counts = result.get_counts()
plot_histogram(counts)
print(c)```
qiskit ×1