human
I am working on the file "PYNQLearn/FabricOnly/.ipynb_checkpoints/myHDL_PYNQZ12_FabricOnly-checkpoint.ipynb".
The first task is:
Verilog Testbench
PYNQ-Z1 Constraints File
Below is what is found in file constrs_S0L0.xdc
Notice that the orgianl port names found in the PYNQ-Z1 Constraints file have been changed to the port names of the module S0L0
Board Verification
Project 4: Basic Duty Cycle
https://timetoexplore.net/blog/arty-fpga-verilog-02
myHDL Code
Can you write Python program for it?

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Give me a found in file constrs_S0L0?
assistant
#Here is found in file constrs_S0L0.

@block
def BDCLed(clk, led):
    counter=Signal(modbv(0)[8:])
    duty_led=Signal(modbv(8)[8:])
    
    @always(clk.posedge)
    def logic():
        counter.next=counter+1
        if counter<duty_led:
            led.next=15
        else:
            led.next=0
    
    return instances()