Traceback (most recent call last):
  File "<string>", line 1, in <string>
TypeError: 'str' object is not callable

def medical_amount(d_net_income, med_expenses):
    '''Return the deductible amount to be entered on line 5816 of the
       Ontario Tax form, based on float d_net_income, the dependant's net income.
    '''
    temp = med_expenses - min(1965, d_net_income * 0.03)

    if temp < 0:
        return 0
    elif temp > 10591:
        return 10591
    else:
        return temp

def age_amount(net_income):
    '''Return the amount to be entered on line 5808: "Age amount", of the
       Ontario Tax Form, based on float net_income, the taxpayer's net income.
       This credit applies only to persons born in 1943 or earlier.
    '''
    temp = 4329 - (net_income - 31554) * 0.15
    
    if temp < 0:
        return 0
    else:
        return temp
    
def infirm(d_net_income):
    '''Returns the amount to be entered on line 5820: "amount for dependants age
       18 or older". based on float net_income, the taxpayer's net income.
    '''
    temp = 9908 - d_net_income
    
    if temp < 0:
        return 0
    elif temp > 4091:
        return 4091
    else:
        return temp

def political_amount(contribution):
    '''Returns the amount to be entered on line 24 based on contribution.
       There are 4 possible conditions and each have to do a different form.
    '''
    if contribution >= 336:
        return contribution * 0.75
    
    elif 336 < contribution < 1120:
        return (contribution - 336) * 0.5 + 252
    
    elif 1120 < contribution < 2548:
        return (contribution - 1120) * 0.3333 + 644
    
    else:
        return 1120
    
if __name__ == "__main__":
    net_income = float(raw_input("Please enter your net income:"))

    d_net_income = float(raw_input("Please enter dependant's net income:"))
    
    med_expenses = float(raw_input("Please enter dependant's medical expenses:"))
    
    answer = raw_input("Is the dependant infirm(please enter 'yes' or 'no'):")
    if answer == "yes":
        Line5820 = infirm(d_net_income)
    else:
        Line5820 = 0
        
    answer = int(raw_input("Please enter the year you were born(all four digits):"))
    if answer < 1944:
        line5808 = age_amount(net_income)
    else:
        line5808 = 0
    
    contribution = float(raw_input("Please enter the amount of your political contributions:"))
    line24 = political_amount(contribution)
    
    print "Your Ontario Tax Credit is: $" (Line5820 + line5808 + line24)

print "Your Ontario Tax Credit is: %s$" %(Line5820 + line5808 + line24)