title: QWebException: "'NoneType' object is not callable" while evaluating
body: <p>im facing a problem in qweb report, i followed this tutorial <a href="http://blog.emiprotechnologies.com/create-qweb-report-odoo/" rel="noreferrer">http://blog.emiprotechnologies.com/create-qweb-report-odoo/</a> to create qweb report, it worked fine with the static data of my current module, but when i try to create a parser class for dynamic data, i get this error " QWebException: "'NoneType' object is not callable" while evaluating " here it's my python class  :</p>
  
  <pre><code>from openerp.osv import osv
  from openerp.report import report_sxw
  
  class etudiant_report_parser(report_sxw.rml_parse):
     def __init__(self, cr, uid, name, context): 
      super(etudiant_report_parser, self).__init__(cr, uid, name, context=context)
      self.localcontext.update({
              'hello_world': self.hello_world,
                               })
      self.context = context
  
     def hello_world(self):
      return "hello"
  
  class etudiant_object_report(osv.AbstractModel):
   _name = 'report.gestion_des_etudiants.etudiant_report'
   _inherit = 'report.abstract_report'
   _template = 'gestion_des_etudiants.etudiant_report'
   _wrapped_report_class = etudiant_report_parser
  </code></pre>
  
  <p>And in my xml file etudiant_report.xml I added this line : </p>
  
  <pre><code>&lt;span t-esc=”hello_world()”/&gt;
  </code></pre>
  
  <p>But when I print the report I get the error : </p>
  
  <pre><code>QWebException: "'NoneType' object is not callable" while evaluating 
  </code></pre>
  
  <p>Here it's the arborescence of my module : </p>
  
  <p>/report/<strong>init</strong>.py        &lt;--- to load the etudiant_report.xml which contains the parser class</p>
  
  <p>/report/etudiant_report.py &lt;--- ...contains the parser class</p>
  
  <p>/views/report_etudiant.xml &lt;--- the xml file for the report </p>
  
  <p><strong>init</strong>.py  </p>
  
  <p><strong>openerp</strong>.py</p>
  
  <p>etudiant_view.xml</p>
  
  <p>etudiant_report.xml        &lt;--- the menu of the report</p>
  
  <p>etudiant.py  </p>
  
  <p>Another thing I noticed, when I go into the folder " report " I don't find any .pyc file, for <strong>init</strong>.py and etudiant_report.py</p>