vector_norm.py

#norm (length or size) of a vector 

norm = v[0]*v[0] + v[1]*v[1] + v[2]*v[2] #v = vector

def norm(v)
	n = v[0]*v[0] + v[1]*v[1] + v[2]*v[2]
	return n 

x = norm(v) #to use the function, define it as "x"