Create a KML Placemark element.

    Args:
      parent: The parent ElementTree.Element instance.
      name: The placemark name as a string.
      style_id: If not None, the id of a style to use for the placemark.
      visible: Whether the placemark is initially visible or not.
      description: A description string or None.

    Returns:
      The placemark ElementTree.Element instance.

def _CreatePlacemark(self, parent, name, style_id=None, visible=True,
                       description=None):
    """Create a KML Placemark element.

    Args:
      parent: The parent ElementTree.Element instance.
      name: The placemark name as a string.
      style_id: If not None, the id of a style to use for the placemark.
      visible: Whether the placemark is initially visible or not.
      description: A description string or None.

    Returns:
      The placemark ElementTree.Element instance.
    """
    placemark = ET.SubElement(parent, 'Placemark')
    placemark_name = ET.SubElement(placemark, 'name')
    placemark_name.text = name
    if description is not None:
      desc_tag = ET.SubElement(placemark, 'description')
      desc_tag.text = description
    if style_id is not None:
      styleurl = ET.SubElement(placemark, 'styleUrl')
      styleurl.text = '#%s' % style_id
    if not visible:
      visibility = ET.SubElement(placemark, 'visibility')
      visibility.text = '0'
    return placemark