A problem with str VS int.

[Steve GS]

 If I enter a one-digit input or a three-digit number, the code works but if I enter a two digit number, the if statement fails and the else condition prevails.

       tsReading = input("   Enter the " + Brand + " test strip reading: ")
        if tsReading == "": tsReading = "0"
        print(tsReading)
        if ((tsReading < "400") and (tsReading >= "0")):
            tsDose = GetDose(sReading)
            print(tsReading + "-" + tsDose)
            ValueFailed = False
        else:
            print("Enter valid sensor test strip Reading.")

I converted the variable to int along with the if statement comparison and it works as expected.
See if it fails for you...

Steve