Run fault with non-zero 1

[JXH-sanitizer]

Thanks for your sharing about the workflow of Pest and flopy. I have tried your codes but in the last cell, it returns a fault called: "
124 if "window" in platform.platform().lower():
125 if ret_val != 0:

126 raise Exception("run() returned non-zero: {0}".format(ret_val))
127 else:
128 estat = os.WEXITSTATUS(ret_val)

Exception: run() returned non-zero: 1" Can you suggest why does it happen? I am not sure. Thank you all in all.