docs: def create(filename, task, alias):
      """Creates a gptool help xml file."""
  
      metadata = ET.Element('metadata', {'xml:lang': 'en'})
      tool = ET.SubElement(metadata, 'tool', name=task.name,
                           displayname=task.display_name,
                           toolboxalias=alias)
  
      summary = ET.SubElement(tool, 'summary')
      summary.text = ''.join((HTML_BEGIN, task.description, HTML_END))
  
      parameters = ET.SubElement(tool, 'parameters')
      for task_param in task.parameters:
          param = ET.SubElement(parameters, 'param',
                                name=task_param['name'],
                                displayname=task_param['display_name']
                               )
          dialog_ref = ET.SubElement(param, 'dialogReference')
          dialog_ref.text = ''.join((HTML_BEGIN, task_param['description'], HTML_END))
          python_ref = ET.SubElement(param, 'pythonReference')
          python_ref.text = ''.join((HTML_BEGIN, task_param['description'], HTML_END))
  
      dataIdInfo = ET.SubElement(metadata, 'dataIdInfo')
      searchKeys = ET.SubElement(dataIdInfo, 'searchKeys')
      keyword1 = ET.SubElement(searchKeys, 'keyword')
      keyword1.text = 'ENVI'
      keyword2 = ET.SubElement(searchKeys, 'keyword')
      keyword2.text = task.name
      idCitation = ET.SubElement(dataIdInfo, 'idCitation')
      resTitle = ET.SubElement(idCitation, 'resTitle')
      resTitle.text = task.name
      idAbs = ET.SubElement(dataIdInfo, 'idAbs')
      idAbs.text = ''.join((HTML_BEGIN, task.description, HTML_END))
      idCredit = ET.SubElement(dataIdInfo, 'idCredit')
      idCredit.text = '(c) 2017 Exelis Visual Information Solutions, Inc.'
      resTitle.text = task.name
      tree = ET.ElementTree(metadata)
      tree.write(filename)