'Get (find) a I{non-attribute} attribute by name.
@param name: A attribute name.
@type name: str
@return: A tuple: the requested (attribute, ancestry).
@rtype: (L{SchemaObject}, [L{SchemaObject},..])'

def get_attribute(self, name):

    for (child, ancestry) in self.attributes():
        if (child.name == name):
            return (child, ancestry)
    return (None, [])
