Problem inserting an element where I want it using lxml

[Josh English]

Here's a trimmed down version of how I did this (using ElementTree standalone, but the API should be the same)
This is from a class definition and the _elem attribute is a link to an ElementTree.Element object.

...
    def _add_elem(self, tagName, text, attrib ={}):
        """_add_elem(tagName, text, attrib={})
        Adds a child element in the appropriate place in the tree.
        Raises an IndexError if the checker does not allow an addition child of tagName.
        """
        last_child = None
        for child in self._elem.findall('.//%s' % tagName):
            last_child = child
     
        if last_child is None:
            new_child = ET.SubElement(self._elem, tagName, attrib)
        else:
            new_child = ET.Element(tagName, attrib)
            self._elem.insert(self._elem._children.index(last_child)+1, new_child)
        new_child.text=str(text)

        return new_child

I don't think you need to count the instances of the bingo node (unless you want to prevent too many from being added in).

Josh