我试图用python和zeep发出SOAP请求，我需要添加一个soap：Header，带有security（wsse：Security）和timestamp（wsu：Timestamp）标签
我有这个代码：

from zeep import Client
from zeep.wsse import UsernameToken
from zeep.wsse import utils
from datetime import datetime, timedelta

# Create a SOAP client for the service
url = 'https://XXXXXXXXX/wsdlXXXXXX'
client = Client(url)

# Create a Object UsernameToken auth credentials
username = 'USERNAME'
password = 'PASSWORD'
token = UsernameToken(username, password)

# Add object UsernameToken to the tag wsse:Security
security = client.get_element('wsse:Security')
security_value = security(namelist=[token])

# Create a object Timestamp with date an time (now)
timestamp = utils.Timestamp()
timestamp_created = datetime.utcnow()
timestamp_expires = timestamp_created + timedelta(minutes=10)
timestamp.created = timestamp_created
timestamp.expires = timestamp_expires

# Add the tag wsu:Timestamp to the hader SOAP
timestamp_value = timestamp.xml

# add the tags in header SOAP
header = client.service._binding.create_message_header()
header.append(security_value)
header.append(timestamp_value)

# Send request SOAP with header
result = client.service.addressTown(_soapheaders=[header], arg1='28001')

我的错误是：

Traceback (most recent call last):
  File "test3.py", line 16, in <module>
    security = client.get_element('wsse:Security')
  File "C:\Users\USER\Documents\Projects\Eva Seguros\comparatupoliza\venv\lib\site-packages\zeep\client.py", line 182, in get_element
    return self.wsdl.types.get_element(name)
  File "C:\Users\USER\Documents\Projects\Eva Seguros\comparatupoliza\venv\lib\site-packages\zeep\xsd\schema.py", line 126, in get_element
    qname = self._create_qname(qname)
  File "C:\Users\USER\Documents\Projects\Eva Seguros\comparatupoliza\venv\lib\site-packages\zeep\xsd\schema.py", line 265, in _create_qname
    raise ValueError("No namespace defined for the prefix %r" % prefix)
ValueError: No namespace defined for the prefix 'wsse'