code: def cart2sph(x, y, z):
      
      r = np.sqrt(x**2 + y**2 + z**2)
      lat = np.arcsin(z/r)
      lon = np.arctan2(y, x)
      return lon, lat
docs: Converts cartesian coordinates `x`, `y`, `z` into a longitude and latitude.
      x=0, y=0, z=0 is assumed to correspond to the center of the globe.
      Returns lon and lat in radians.
  
      Parameters
      ----------
      `x`, `y`, `z` : Arrays of cartesian coordinates
  
      Returns
      -------
      lon : Longitude in radians
      lat : Latitude in radians