class_docstr: Class for modeling a non-linear 2D localization problem.
  
  The state is composed of a planar orientation and position, and is thus a
  member of SE(2).
  A sensor provides the linear and angular speed, while another one provides
  sparse position observations.
docstr: Model used to create the measurements.
  
  This model simply outputs the position part of the state, i.e. its
  two last elements.
  
  Parameters
  ----------
  state : array-like, shape=[dim]
      Vector representing the state.
  
  Returns
  -------
  observation : array-like, shape=[dim_obs]
      Expected observation of the state.
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code: def observation_model(self, state):
      """Model used to create the measurements.
  
      This model simply outputs the position part of the state, i.e. its
      two last elements.
  
      Parameters
      ----------
      state : array-like, shape=[dim]
          Vector representing the state.
  
      Returns
      -------
      observation : array-like, shape=[dim_obs]
          Expected observation of the state.
      """
      return state[self.group.rotations.dim :]
  
imports: import geomstats.backend
  from geomstats.geometry.euclidean import Euclidean
  from geomstats.geometry.matrices import Matrices
  from geomstats.geometry.special_euclidean import SpecialEuclidean
label_desc: Use image node_id 11 for calling the Localization obj's underlying member method code with example usage: obj.observation_model(state) and returns: state