def addItem(self, child, href):
assert isinstance(child, Base), "<STR_LIT>"<EOL>child.setHref(href)<EOL>for item in self.items:<EOL><INDENT>assert item.href != href, "<STR_LIT>"+href<EOL><DEDENT>self.items += [child]           <EOL>return<EOL>
Add a new item (a catalogue or resource) as a child of this catalogue.