def annuity(rate, C, months, rate_check, month_check): 
    if str(rate_check) == "percent": 
        rate=rate/100
        
    if str(month_check) == 'year': 
        months = months*12
        
    PV = (C/rate)*(1-(1/(1+rate)**months))
    annuity = PV + C
    print("The annuity is: {:.2f}$".format(annuity))
    
def perpetuity(rate, C, rate_check): 
        if str(rate_check) == "percent": 
            rate = rate/100
            
        PV = C/rate
        print("The perpetuity of your deposit is: {:.2f}$".format(PV))
        
def futureValue(rate, PV, months, rate_check, month_check):
        if str(rate_check) == "percent": 
            rate = rate/100
        
        if str(month_check) == "year": 
            months = months*12
        
        FV = float(PV)*(1+float(rate))**float(months)
        print("The future value of your deposit is: {:.2f}$".format(FV))
    
def presentValue(rate, FV, months, rate_check, month_check): 
        if str(rate_check) == "percent": 
            rate = rate/100
        
        if str(month_check) == "year": 
            months = months*12
            
        PV = float(FV)/((1+float(rate))**float(months))
        print("The present value of your deposit is: {:.2f}$".format(PV))

annuity(0.12, 1000, 12, "NA", 'months')

The annuity is: 7194.37$

perpetuity(12, 1000, 'percent')

The perpetuity of your deposit is: 8333.33$

futureValue(0.12, 1000, 12, 'NA', 'months')

The future value of your deposit is: 3895.98$

presentValue(12, 1000, 1, 'percent', 'year')

The present value of your deposit is: 256.68$