class_docstr: Class for space of landmarks.
  
  The landmark space is a product manifold where all manifolds in the
  product are the same. The default metric is the product metric and
  is often referred to as the L2 metric.
  
  Parameters
  ----------
  ambient_manifold : Manifold
      Manifold to which landmarks belong.
  k_landmarks : int
      Number of landmarks.
docstr: Metric to equip the space with if equip is True.
docstr_tok: ["Metric","to","equip","the","space","with","if","equip","is","True","."]
code: def default_metric():
      """Metric to equip the space with if equip is True."""
      return L2LandmarksMetric
  
imports: from geomstats.geometry.nfold_manifold import NFoldManifold, NFoldMetric
label_desc: Use image node_id 3 for calling the Landmarks obj's underlying member method code with example usage: obj.default_metric() and returns: L2LandmarksMetric