docs: def bounds(arg):
      """Converts a lat/lon bounds to a comma- and pipe-separated string.
  
      Accepts two representations:
      1) string: pipe-separated pair of comma-separated lat/lon pairs.
      2) dict with two entries - "southwest" and "northeast". See convert.latlng
      for information on how these can be represented.
  
      For example:
  
      sydney_bounds = {
          "northeast" : {
              "lat" : -33.4245981,
              "lng" : 151.3426361
          },
          "southwest" : {
              "lat" : -34.1692489,
              "lng" : 150.502229
          }
      }
  
      convert.bounds(sydney_bounds)
      # '-34.169249,150.502229|-33.424598,151.342636'
  
      :param arg: The bounds.
      :type arg: dict
      """
  
      if is_string(arg) and arg.count("|") == 1 and arg.count(",") == 2:
          return arg
      elif isinstance(arg, dict):
          if "southwest" in arg and "northeast" in arg:
              return "%s|%s" % (latlng(arg["southwest"]),
                                latlng(arg["northeast"]))
  
      raise TypeError(
          "Expected a bounds (southwest/northeast) dict, "
          "but got %s" % type(arg).__name__)