Convert List and Dataframe to a DATAFRAME

I have a DF called "billing".

<?xml version="1.0" encoding="ISO-8859-1" ?>


<test:TASS xmlns="http://www.vvv.com/schemas"  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"  xsi:schemaLocation="http://www.vvv.com/schemas http://www.vvv.com/schemas/testV2_02_03.xsd"  xmlns:test="http://www.vvv.com/schemas">
    <test:house>
                <test:billing>
                    <test:proceduresummary>
                        <test:guidenumber>X2030</test:guidenumber>
                            <test:diagnosis>
                                <test:table>ICD-10</test:table>
                                <test:diagnosiscod>J441</test:diagnosiscod>
                                <test:description>CHRONIC OBSTRUCTIVE PULMONARY DISEASE WITH (ACUTE) EXACERBATION</test:description>
                            </test:diagnosis>
                            <test:procedure>
                                <test:procedure>
                                    <test:description>HOSPITAL</test:description>
                                </test:procedure>
                                <test:amount>12</test:amount>
                            </test:procedure>
                    </test:proceduresummary>
                </test:billing>
                    <test:billing>
                    <test:proceduresummary>
                        <test:guidenumber>Y6055</test:guidenumber>
                            <test:diagnosis>
                                <test:table>ICD-10</test:table>
                                <test:diagnosiscod>I21</test:diagnosiscod>
                                <test:description>ACUTE MYOCARDIAL INFARCTION</test:description>
                            </test:diagnosis>
                            <test:procedure>
                                <test:procedure>
                                    <test:description>HOSPITAL</test:description>
                                </test:procedure>
                                <test:amount>8</test:amount>
                            </test:procedure>
                    </test:proceduresummary>
                </test:billing>
                    <test:billing>
                    <test:proceduresummary>
                        <test:guidenumber>Z9088</test:guidenumber>
                            <test:diagnosis>
                                <test:table>ICD-10</test:table>
                                <test:diagnosiscod>F20</test:diagnosiscod>
                                <test:description>SCHIZOPHRENIA</test:description>
                            </test:diagnosis>
                            <test:procedure>
                                <test:procedure>
                                    <test:description>HOSPITAL</test:description>
                                </test:procedure>
                                <test:amount>1</test:amount>
                            </test:procedure>
                    </test:proceduresummary>
                </test:billing>
    </test:house>
</test:TASS>

My code:

require(tidyverse)
require(xml2)
setwd("D:/")
page<- read_xml("base.xml")

To dataframe:

ns<- page %>% xml_find_all(".//test:billing")
billing<-xml2::as_list(ns) %>% jsonlite::toJSON() %>% jsonlite::fromJSON()

See example: for each variable there are other variables (list or dataframe). I would like to transform these subvariables into standard variables (integer, character, ...) and build a DF without these hidden variables (list and dataframe). It is possible?

DF should look like this.

guidenumber<- c('X2030','Y6055','Z9088')
table<- c('ICD-10','ICD-10','ICD-10')
diagnosiscod<- c('J441','I21','F20')
description<- c('CHRONIC OBSTRUCTIVE PULMONARY DISEASE WITH (ACUTE) EXACERBATION','ACUTE MYOCARDIAL INFARCTION','SCHIZOPHRENIA')
procedure<- c('HOSPITAL','HOSPITAL','HOSPITAL')
amount<- c(12,8,1)
DF<- data.frame(guidenumber,table,diagnosiscod,description,procedure,amount)