import calendar, datetime as dt
dD, c, dowx, datex = dt.timedelta(days=1), 0, 6, 1
Y1, M1, D1,   Y2, M2, D2 = 1901,1,1,   2000,12,31

dY = Y2-Y1 #num of years
Y1 = (Y1%400) + 400 #normalized and non-zero
a = dt.datetime(Y1, M1, D1)
b = dt.datetime(Y1+dY, M2, D2)

while a <= b:
	if a.day==datex and a.weekday()==dowx: c+=1; dD=dt.timedelta(days=7)
	a += dD

print calendar.day_name[dowx],"on day", datex, "of the month", c