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Given the following text description, write Python code to implement the functionality described below step by step
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Description:
 Start by defining a Python function that we want to compute.
Step1:  Generate a circuit that computes this function. To implement the logical operations we use  standard verilog gates, which are available in mantle.verilog.gates.
Step2:  Next, generate a verilator test harness in C++ for the circuit. The test vectors are generated using the python function f. The verilator test bench compares the output of the simulator to those test vectors.
Step3:  Using fault, we can use the same tester and (with the same testbench inputs/expectations) and use a different backend, like the python simulator.
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Python Code:
def f(a, b, c):
    return (a & b) ^ c
Explanation: Start by defining a Python function that we want to compute.
End of explanation
import magma as m
import mantle
class VerilatorExample(m.Circuit):
    io = m.IO(a=m.In(m.Bit), b=m.In(m.Bit), c=m.In(m.Bit), d=m.Out(m.Bit))
    io.d <= f(io.a, io.b, io.c)
m.compile("build/VerilatorExample", VerilatorExample, "coreir-verilog", inline=True)
%cat build/VerilatorExample.v
Explanation: Generate a circuit that computes this function. To implement the logical operations we use  standard verilog gates, which are available in mantle.verilog.gates.
End of explanation
from itertools import product
from fault import Tester
tester = Tester(VerilatorExample)
for a, b, c in product([0, 1], [0, 1], [0, 1]):
    tester.poke(VerilatorExample.a, a)
    tester.poke(VerilatorExample.b, b)
    tester.poke(VerilatorExample.c, c)
    tester.eval()
    tester.expect(VerilatorExample.d, f(a, b, c))
tester.print("done!!")
tester.compile_and_run("verilator", directory="build")
%cat build/VerilatorExample_driver.cpp
Explanation: Next, generate a verilator test harness in C++ for the circuit. The test vectors are generated using the python function f. The verilator test bench compares the output of the simulator to those test vectors.
End of explanation
tester.compile_and_run("python")
Explanation: Using fault, we can use the same tester and (with the same testbench inputs/expectations) and use a different backend, like the python simulator.
End of explanation
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