Python 运算符优先级

#!/usr/bin/python

a = 20
b = 10
c = 15
d = 5
e = 0

e = (a + b) * c / d       #( 30 * 15 ) / 5
print "Value of (a + b) * c / d is ",  e

e = ((a + b) * c) / d     # (30 * 15 ) / 5
print "Value of ((a + b) * c) / d is ",  e

e = (a + b) * (c / d);    # (30) * (15/5)
print "Value of (a + b) * (c / d) is ",  e

e = a + (b * c) / d;      #  20 + (150/5)
print "Value of a + (b * c) / d is ",  e