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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 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