Any tag test case.

any_type_test.py

#!/usr/bin/env python

from lxml import etree

from rpclib.model.primitive import AnyXml
from rpclib.model.complex import ComplexModel
from rpclib.const import xml_ns as ns
from rpclib.util.xml import get_schema_documents

class SomeType(ComplexModel):
    __namespace__ = "zo"

    anything = AnyXml(schema_tag='{%s}any' % ns.xsd, namespace='##other',
                                                         process_contents='lax')

docs = get_schema_documents([SomeType])

print etree.tostring(docs['tns'], pretty_print=True)

output.xml

<xs:schema xmlns:wsa="http://schemas.xmlsoap.org/ws/2003/03/addressing" xmlns:tns="zo" xmlns:plink="http://schemas.xmlsoap.org/ws/2003/05/partner-link/" xmlns:xop="http://www.w3.org/2004/08/xop/include" xmlns:senc="http://schemas.xmlsoap.org/soap/encoding/" xmlns:s12env="http://www.w3.org/2003/05/soap-envelope/" xmlns:s12enc="http://www.w3.org/2003/05/soap-encoding/" xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:wsdl="http://schemas.xmlsoap.org/wsdl/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:senv="http://schemas.xmlsoap.org/soap/envelope/" xmlns:soap="http://schemas.xmlsoap.org/wsdl/soap/" targetNamespace="zo" elementFormDefault="qualified">
  <xs:complexType name="SomeType">
    <xs:sequence>
      <xs:any namespace="##other" processContents="lax" minOccurs="0" nillable="true"/>
    </xs:sequence>
  </xs:complexType>
  <xs:element name="SomeType" type="tns:SomeType"/>
</xs:schema>

https://github.com/plq/rpclib/blob/ee7752464688badf90cbb36416b4c5fa6c81e809/src/rpclib/test/interface/test_xml_schema.py