(Bug fix) Convert "valid" variable to boolean in "compare_sn" function

lemi2seed/utils.py

@@ -83,7 +83,8 @@ def compare_sn(equipment: str, sn: str, data_input: Optional[str] = None) -> boo
                          "({} != {}). Please correct!".format(equipment, sn, data_input))
     else:
         valid = re.match(r"^\d{3}$", str(sn))  # type: ignore
-        if valid is None:
+        valid = False if valid is None else True
+        if not valid:
             logger.error("The serial number of the {} should be 3 digits "
                          "long.".format(equipment))
     return valid