How to use the pykml.parser.parse function in pykml

def get_boundaries():
    """ Parse the KML file to get the boundaries
    """
    with open(kml_file) as f:
        tree = parser.parse(f)
        root = tree.getroot()

        N = 0
        placemarks = {}
        for ch in root.Document.Folder.getchildren():
            if 'Placemark' in ch.tag:
                # Found a placemark
                N += 1
                pname = int(ch.name.text)
                
                # Get the coordinates
                pcoords = ch.MultiGeometry.Polygon.outerBoundaryIs.LinearRing.coordinates.text
                pcoords = pcoords.strip()
                pcoords = re.split(',| ', pcoords)
                pcoords = [float(c) for c in pcoords]

from lxml import etree

# define variables for the namespace URL strings
kmlns = '{}' #'{' + nsmap['kml'] + '}'
gxns = '{' + nsmap['gx'] + '}'

# start with a base KML tour and playlist
tour_doc = KML.kml(
    GX.Tour(
      KML.name("Play me!"),
      GX.Playlist(),
    )
)

with open("colorado_river_linestring.kml") as f:
    linestring_doc = parse(f)

# get the coordinate string of the first KML coordinate element
coord_str = str(
    linestring_doc.getroot().find(".//{http://www.opengis.net/kml/2.2}coordinates")
).strip()

for vertex in coord_str.split(' '):
    (lon,lat,alt) = vertex.split(',')
    flyto = GX.FlyTo(
        GX.duration(2),
        GX.flyToMode("smooth"),
        KML.Camera(
          KML.longitude(lon),
          KML.latitude(lat),
          KML.altitude(0),
          KML.heading(-129.7),

- if data_fields requested:
        a struct with attributes:
          * 'geometry': a |shapely| Polygon/MultiPolygon or Point/MultiPoint
          * the requested data_fields as attributes. The value are string, or None
            if the data fields is unset in the KML. If several identical data_fields are
            found, they are put in a list.
  """
  if kml_path.endswith('kmz'):
    with zipfile.ZipFile(kml_path) as kmz:
      kml_name = [info.filename for info in kmz.infolist()
                  if os.path.splitext(info.filename)[1] == '.kml'][0]
      with kmz.open(kml_name) as kml_file:
        root = parser.parse(kml_file).getroot()
  else:
    with open(kml_path, 'r') as kml_file:
      root = parser.parse(kml_file).getroot()
  tag = root.tag[:root.tag.rfind('}')+1]
  zones = {}
  for element in root.findall('.//' + tag + root_id_zone):
    # Ignore nested root_id within root_id
    if element.find('.//' + tag + root_id_zone) is not None:
      continue
    if ignore_if_parent is not None and element.getparent().tag.endswith(ignore_if_parent):
      continue

    name = element.name.text
    # Read the zone geometry
    geometry = None
    polygons = [_GetPolygon(poly)
                for poly in element.findall('.//' + tag + 'Polygon')]
    if polygons:
      if len(polygons) == 1:

def ReadKML(filename):
  with open(filename, 'r') as kml_file:
    doc = parser.parse(kml_file).getroot()
    return doc

def _ReadKmlBorder(kml_path, root_id='Placemark'):
  """Gets the border defined in a KML.

  Args:
    kml_path: The path name to the border file KML or KMZ.
    root_id_zone: The root id defininig a zone. Usually it is 'Placemark'.

  Returns:
    A dictionary of |shapely| LineString keyed by their names.
  """
  if kml_path.endswith('kmz'):
    with zipfile.ZipFile(kml_path) as kmz:
      kml_name = [info.filename for info in kmz.infolist()
                  if os.path.splitext(info.filename)[1] == '.kml'][0]
      with kmz.open(kml_name) as kml_file:
        root = parser.parse(kml_file).getroot()
  else:
    with open(kml_path, 'r') as kml_file:
      root = parser.parse(kml_file).getroot()

  tag = root.tag[:root.tag.rfind('}') + 1]
  linetrings_dict = {}
  for element in root.findall('.//' + tag + root_id):
    # Ignore nested root_id within root_id
    if element.find('.//' + tag + root_id) is not None:
      continue
    name = element.name.text
    linestrings = [
        _GetLineString(l)
        for l in element.findall('.//' + tag + 'LineString')
    ]
    if not linestrings:

def ReadKML(filename):
  with open(filename, 'r') as kml_file:
    doc = parser.parse(kml_file).getroot()
    return doc