import lxml.etree as etree

def inject(doc, add_ele, out_fufi=None):
    if(isinstance(doc, str)):
        ### allow for a file as the first argument
        parser = etree.XMLParser(remove_blank_text=True)
        doc = etree.parse(doc, parser)
    doc_root_ele = doc.getroot()
    #foo = type(add_doc)
    #print(foo)
    #quit()
    #if isinstance('lxml.etree._Element', doc_root_ele):
    #    print("ele")
    #    quit()
    #add_doc_root_ele = add_doc.getroot()
    doc_root_ele.append(add_ele)
    if out_fufi is not None:
        doc.write(out_fufi, pretty_print=True)
    return doc


def show(doc, do_verbose=False):
    string = etree.tostring(doc, pretty_print=True).decode()
    if do_verbose:
        print(string)
    return string