code: def univariate_fisher_rao_dist(point_a, point_b):
      mean_a = point_a[..., 0]
      mean_b = point_b[..., 0]
      sigma_a = point_a[..., 1]
      sigma_b = point_b[..., 1]
  
      sdiff_mean = (mean_a - mean_b) ** 2
      sdiff_sigma = (sigma_a - sigma_b) ** 2
      ssum_sigma = (sigma_a + sigma_b) ** 2
  
      return (
          2
          * gs.sqrt(2)
          * gs.arctanh(
              gs.sqrt(
                  (sdiff_mean + 2 * sdiff_sigma)
                  / (sdiff_mean + 2 * ssum_sigma)
              )
          )
      )
  
imports: import pytest
  import geomstats.backend
  from geomstats.test_cases.geometry.pullback_metric import PullbackDiffeoMetricTestCase
label_desc: Use image node_id 1 for calling a global function with example usage: univariate_fisher_rao_dist(point_a, point_b) and returns: unknown