code: def circumcircle_radius_2(pt0, pt1, pt2):
      r
      a = distance(pt0, pt1)
      b = distance(pt1, pt2)
      c = distance(pt2, pt0)
  
      t_area = triangle_area(pt0, pt1, pt2)
      prod2 = a * b * c
  
      if t_area > 0:
          radius = prod2 * prod2 / (16 * t_area * t_area)
      else:
          radius = np.nan
  
      return radius
docs: r"""Calculate and return the squared radius of a given triangle's circumcircle.
  
      This is faster than calculating radius but should only be used with comparable ratios.
  
      Parameters
      ----------
      pt0: (x, y)
          Starting vertex of triangle
      pt1: (x, y)
          Second vertex of triangle
      pt2: (x, y)
          Final vertex of a triangle
  
      Returns
      -------
      r: float
          circumcircle radius
  
      See Also
      --------
      circumcenter