Adding subelement with ElementTree

Question

The below code, which should add a subelemenet to a given XML element, gives the error:

xml.SubElement(new,xml.Element(self.XMLEntriesList['RiverCallPower'])) TypeError: must be xml.etree.ElementTree.Element, not None

But when I check, the element in question is confirmed to be an Element , and not None .

self.XMLEntriesList['RiverCallPower']
Out[3]: Element 'RiverCallPower' at 0x04B83420

What am I doing wrong?

    import xml.etree.ElementTree as xml
    self.tree = xml.parse('strategies.xml')
    self.root = self.tree.getroot()
    ...
    new=self.root.append(xml.Element('newElement'))
    xml.SubElement(new,xml.Element(self.XMLEntriesList['RiverCallPower']))

Answer 1

I suspect the problem is not in the XMLEntriesList['RiverCallPower'] part, but the new variable that is None . And that happen because append() simply adds the new element to the list of root element's children and doesn't return anything. Try this way :

.......
new = xml.Element('newElement')
self.root.append(new)
xml.SubElement(new,xml.Element(self.XMLEntriesList['RiverCallPower']))