code: def generate_well_behaved_matrix():
      """Generate a matrix with real eigenvalues."""
      matrix = 2 * SPDMatrices(n=3).random_point()
      return matrix
  
file_path: geomstats/examples/gradient_descent_s2.py
imports: import logging
  import matplotlib
  import matplotlib.animation
  import matplotlib.pyplot
  import numpy
  import geomstats.backend
  import geomstats.visualization
  from geomstats.geometry.hypersphere import Hypersphere
  from geomstats.geometry.spd_matrices import SPDMatrices
label_desc: Use image node_id 3 for calling a global function with example usage: generate_well_behaved_matrix() and returns: matrix