沒有測資，實在找不出來，高手可否指教，錯在哪?

#-------------------------------------------------------------------------------

dict={'January':'1','February':'2','March':'3','April':'4','May':'5','June':'6','July':'7','August':'8','September':'9','October':'10','November':'11','December':'12'}
def YEAR(x):
if((x%4==0 and x%100!=0) or x%400==0): return True

n = int(input())
for Case in range(n):
    s1 = input().split()
    s1[1] = s1[1].replace(',','')
    s1[0] = dict[s1[0]]
    s1 = list(map(int,s1))

    s2 = input().split()
    s2[1] = s2[1].replace(',','')
    s2[0] = dict[s2[0]]
    s2 = list(map(int,s2))

    y1 = s1[2] 
    while(y1<=s2[2]): #find the 1st leap year
        if(YEAR(y1)==True): break
        else: y1+=1

    Yn = 0
    if(y1>s2[2]): Yn=0 #no leap years
    else:
        Yn = (s2[2]-y1)//4 + 1 #cal. how many leap years
        #print('@@@ ',y1,Yn)
        if(s1[2]==y1): #if 1st year is leap
            d1 = y1*10000 + s1[0]*100 + s1[1]
            d0 = y1*10000 + 229
            if(d1>d0): Yn-=1
            #print('###',d1,d0,Yn)
        if(YEAR(s2[2])): #if last year is leap
            d2 = s2[2]*10000 + s2[0]*100 + s2[1]
            d0 = s2[2]*10000 + 229
            if(d2<d0): Yn-=1
            #print('###',d1,d0,Yn)
    print('Case %d: %d' %(Case+1,Yn))