code: def similarity_transform(vertices, s, R, t3d):
      """similarity transform. dof = 7.
      3D: s*R.dot(X) + t
      Homo: M = [[sR, t],[0^T, 1]].  M.dot(X)
      Args:(float32)
          vertices: [nver, 3].
          s: [1,]. scale factor.
          R: [3,3]. rotation matrix.
          t3d: [3,]. 3d translation vector.
      Returns:
          transformed vertices: [nver, 3]
      """
      t3d = np.squeeze(np.array(t3d, dtype=np.float32))
      transformed_vertices = s * vertices.dot(R.T) + t3d[np.newaxis, :]
  
      return transformed_vertices
  
file_path: insightface/python-package/insightface/thirdparty/face3d/mesh/transform.py
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import numpy
  import math
  from math import cos, sin
label_desc: Use image node_id 4 for calling a global function with example usage: similarity_transform(vertices, s, R, t3d) and returns: transformed_vertices