title: How to add attributes to SOAP envelope part, using suds?
body: <p>I have WSDL server with some methods, each methods accepts DataModelType.
  Earlier I used it this way:</p>
  
  <pre><code>import suds.transport.http
  from suds.client import Client
  
  trans = suds.transport.http.HttpAuthenticated(username=username,
                                                password=password)
  __client = Client(url, transport=trans)
  func = __client.service.__getattr__("ReceiveData")
  argument = __client.factory.create('DataModelType')
  argument["Key"] = "0001" 
  return func(argument)
  </code></pre>
  
  <p>And it perfectly worked.</p>
  
  <p>It created XML with DataRequest automatically:</p>
  
  <pre><code>&lt;Envelope&gt;
    &lt;Body&gt;
      &lt;DataRequest&gt;
        &lt;DataModelType&gt;
          &lt;Key&gt;0001&lt;/Key&gt;
           &lt;Data&gt;&lt;/Data&gt;
        &lt;/DataModelType&gt;
      &lt;/DataRequest&gt;
    &lt;/Body&gt;
  &lt;/Envelope&gt;
  </code></pre>
  
  <p>Sent it, and as response I got something like:</p>
  
  <pre><code>&lt;Envelope&gt;
    &lt;Body&gt;
      &lt;DataResponse&gt;
        &lt;DataModelType&gt;
          &lt;Key&gt;0001&lt;/Key&gt;
          &lt;Data&gt;"Help me solve that magic, please"&lt;/Data&gt;
        &lt;/DataModelType&gt;
      &lt;/DataResponse&gt;
    &lt;/Body&gt;
  &lt;/Envelope&gt;
  </code></pre>
  
  <p>And <strong>return func(argument)</strong> gave me back python object built from <strong>DataModelType</strong></p>
  
  <p>Now I found that tag <em>DataRequest</em> has parameters that I have to set for server to receive right response. But how should I set them pythonic throw <strong>suds</strong>, not exstracting XML, parsing it, and then send it by http transport?</p>
  
  <p>If sending by http transport is just one way, how to do it? I'm trying to simulate what is going inside <strong>return func(argument)</strong>, but even if it takes exactly the same parameters, result is different.</p>
  
  <p>Is there interface in suds to set properties of convert that it cares of by himself? How to solve that task?</p>