'Set an attribute\'s value.
@param name: The name of the attribute.
@type name: basestring
@param value: The attribute value.
@type value: basestring
@see: __setitem__()'

def set(self, name, value):

    attr = self.getAttribute(name)
    if (attr is None):
        attr = Attribute(name, value)
        self.append(attr)
    else:
        attr.setValue(value)
