import  math

def euclideanDistance(instance1,instance2,length):
    distance=0
    for x in range(length):
        distance+=pow(instance1[x]-instance2[x],2)
    return math.sqrt(distance)

data1=[2,2,2,'a']
data2=[4,4,4,'b']

distance = euclideanDistance(data1,data2,3)

print 'Distance: '+repr(distance)