my line 5 if keeps getting an error, I assume my logic is correct can not for the life of me understand why if is invalid [on hold]

def rainFall(years,month,monthTally) :
    for count in range(1,years+1):
        for count in range(1,13):
            rainfall = int(input("Inches of Rain for month: ",month)
            if month == 1:
                jan = rainfall
            elif month == 2:
                feb = rainfall + feb
            elif month == 3:
                mar = rainfall + mar
            elif month == 4:
                apr = rainfall + apr
            elif month == 5:
                may = rainfall + may
            elif month == 6:
                jun = rainfall + jun
            elif month == 7:
                jul = rainfall + jul
            elif month == 8:
                aug = rainfall + aug
            elif month == 9:
                sep = rainfall + sep
            elif month == 10:
                octo = rainfall + octo
            elif month == 11:
                nov = rainfall + nov
            elif month == 12:
                dec = rainfall + dec
            month = month + 1
            monthTally = monthTally + 1
    totalInches = jan + feb + mar + apr + may + jun + jul + aug + sep + octo + nov + dec
    rainAvg = totalInches/12
    print("Number of months: ", monthTally, "\nTotal inches of rainfall: ", totalInches,"n/Rainfall monthly average: " ,rainAvg)



years = int(input("Enter amount of years: "))

month = 1

monthTally = 1


rainFall(years,month,monthTally)