extracting XML data into datframe

[hey_arnold]

I am querying an API that returns the following, I am trying to extract the name and flow rate data using the below code, but can't work out why its not working?

b'<?xml version="1.0" encoding="utf-8"?>
<soap:Envelope xmlns:soap="http://www.w3.org/2003/05/soap-envelope" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
<soap:Body><GetInstantaneousFlowDataResponse xmlns="http://www.NationalGrid.com/EDP/UI/"><GetInstantaneousFlowDataResult>
<ReportName xmlns="http://www.NationalGrid.com/EDP/BusinessEntities/Public">Instantaneous Flow Report</ReportName>
<PublishedTime xmlns="http://www.NationalGrid.com/EDP/BusinessEntities/Public">2018-07-29T10:47:01</PublishedTime>
<EDPReportPage xmlns="http://www.NationalGrid.com/EDP/BusinessEntities/Public">
<PageName>page1</PageName>
<CurrentGasDay>2018-07-29T00:00:00</CurrentGasDay>
<EDPEnergyGraphTableCollection>
<EDPEnergyGraphTableBE>
<EDPEnergyGraphTableName>table1</EDPEnergyGraphTableName>
<ItemPosition>1</ItemPosition>
<EDPObjectCollection><EDPObjectBE>
<EDPObjectName>ALDBROUGH</EDPObjectName>
<EnergyDataList><EDPEnergyDataBE>
<ApplicableAt>2018-07-29T10:36:00</ApplicableAt>
<FlowRate>0</FlowRate>
<QualityIndicator />
<ScheduleTime>2018-07-29T10:48:00</ScheduleTime>
</EDPEnergyDataBE><EDPEnergyDataBE>
<ApplicableAt>2018-07-29T10:38:00</ApplicableAt>
<FlowRate>0</FlowRate>
<QualityIndicator />
<ScheduleTime>2018-07-29T10:48:00</ScheduleTime>
</EDPEnergyDataBE><EDPEnergyDataBE>
<ApplicableAt>2018-07-29T10:40:00</ApplicableAt>
<FlowRate>0</FlowRate><QualityIndicator

import requests
from lxml import etree
    
fromDate = "2018-07-29"

def getXML():
    url="http://energywatch.natgrid.co.uk/EDP-PublicUI/PublicPI/InstantaneousFlowWebService.asmx"
    headers = {'content-type': 'application/soap+xml; charset=utf-8'}
    body ="""<soap12:Envelope xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:soap12="http://www.w3.org/2003/05/soap-envelope">
  <soap12:Body>
    <GetInstantaneousFlowData xmlns="http://www.NationalGrid.com/EDP/UI/" />
  </soap12:Body>
</soap12:Envelope>"""

    response = requests.post(url,data=body,headers=headers)
    return response.content

import pandas as pd
df1 = pd.DataFrame(columns=("name","value"))   
for pd_date in pd.date_range(fromDate, periods=1):
    day = pd_date.strftime('%Y-%m-%d')
     
    root = etree.fromstring(getXML())
     
    #map prefix 'd' to the default namespace URI
    ns = {'d': 'http://www.NationalGrid.com/EDP/UI/'}
     
    publication_objects = root.xpath('//d:EDPObjectCollection', namespaces=ns)
     
    for obj in publication_objects:
        name = obj.find('d:EDPObjectName', ns).text
     
        for data in obj.findall('d:EnergyDataList/d:EDPEnergyDataBE', ns):
            value = float(data.find('d:FlowRate', ns).text)
        
            df1.loc[len(df1) +1] = [name, value]