With example class:

class A {
    public int i = 3;
    public Integer i2 = 2;
    private int j = 7;
    Set<Character> chars = null;
}

To turn objects into strings:

A a = new A();
String out = Statics.toPyon(a);
// "A(i=3,i2=2,j=7,chars=null)"

To create instance of objects:

Statics.register(A.class);
Pyob pyob1 = (Pyob) Parser.parse("A(i=3,i2=2,j=7,chars=['a','b'])");
Object obj = Statics.fromPyob(pyob1);
assertTrue(obj instanceof A);