def serialize_instance(instance):
    '''
    Serialize an *instance* from a metamodel.
    '''
    attr_count = 0
    metaclass = xtuml.get_metaclass(instance)
    s = 'INSERT INTO %s VALUES (' % metaclass.kind
    for name, ty in metaclass.attributes:
        value = getattr(instance, name)
            
        s += '\n    '
        s += serialize_value(value, ty)

        attr_count += 1
        if attr_count < len(metaclass.attributes):
            s += ', -- %s : %s' % (name, ty)
        else:
            s += ' -- %s : %s' % (name, ty)

    s += '\n);\n'

    return s
Serialize an *instance* from a metamodel.