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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 _StopStyleSelectionMethod(self, doc):
 """Create a method to determine which style to apply to a stop placemark. Args: doc: the KML document. Returns: A function that should accept a Stop argument and return a tuple of (stop placemark style id, pathway placemark style id). Either style id can be None, indicating no style should be set. Given a Stop, we need to determine what KML style to apply to the stops' placemark. In the most basic case, no styling is applied. However, if show_stop_hierarchy is enabled, we style each type of stop differently depending on if the stop is a station, platform, entrance, etc. This method returns a function that is used to pick which style id should be associated with a stop placemark, or None if no style should be applied. It also optionally returns a style id to associate with any line-string connections associated with a stop (eg. to show the pathway between an entrance and a station). """

    if not self.show_stop_hierarchy:
      return lambda stop: (None, None)

    # Create the various styles for showing the stop hierarchy
    self._CreateStyle(
        doc, 'stop_entrance', {'IconStyle': {'color': 'ff0000ff'}})
    self._CreateStyle(
        doc,
        'entrance_connection',
        {'LineStyle': {'color': 'ff0000ff', 'width': '2'}})
    self._CreateStyle(
        doc, 'stop_platform', {'IconStyle': {'color': 'ffff0000'}})
    self._CreateStyle(
        doc,
        'platform_connection',
        {'LineStyle': {'color': 'ffff0000', 'width': '2'}})
    self._CreateStyle(
        doc, 'stop_standalone', {'IconStyle': {'color': 'ff00ff00'}})

    def StyleSelectionMethod(stop):
      if stop.location_type == transitfeed.Stop.LOCATION_TYPE_STATION:
        return ('stop_station', None)
      elif stop.location_type == googletransit.Stop.LOCATION_TYPE_ENTRANCE:
        return ('stop_entrance', 'entrance_connection')
      elif stop.parent_station:
        return ('stop_platform', 'platform_connection')
      return ('stop_standalone', None)

    return StyleSelectionMethod