examples: enhance the call_v_from_python example, with a fn accepting 2 f64 params (#13480)

examples/call_v_from_python/test.py

@@ -1,8 +1,11 @@
 from ctypes import *
-import os
+import math, os
 
 so_file="./test.so"
 if os.name=="nt":
   so_file="./test.dll"
-my_functions = CDLL(so_file)
-print(my_functions.square(10))
+lib = CDLL(so_file)
+assert lib.square(10) == 100, "Cannot validate V square()."
+
+lib.sqrt_of_sum_of_squares.restype = c_double
+assert lib.sqrt_of_sum_of_squares(c_double(1.1), c_double(2.2)) == math.sqrt(1.1*1.1 + 2.2*2.2), "Cannot validate V sqrt_of_sum_of_squares()."

examples/call_v_from_python/test.v

@@ -1,6 +1,13 @@
 module test
 
+import math
+
 [export: 'square']
 fn square(i int) int {
 	return i * i
 }
+
+[export: 'sqrt_of_sum_of_squares']
+fn sqrt_of_sum_of_squares(x f64, y f64) f64 {
+	return math.sqrt(x * x + y * y)
+}