code: def grad_solve_triangular(ans, a, b, trans=0, lower=False, **kwargs):
      tri = anp.tril if (lower ^ (_flip(a, trans) == "N")) else anp.triu
      transpose = lambda x: x if _flip(a, trans) != "N" else x.T
      al2d = lambda x: x if x.ndim > 1 else x[..., None]
  
      def vjp(g):
          v = al2d(
              solve_triangular(a, g, trans=_flip(a, trans), lower=lower)
          )
          return -transpose(tri(anp.dot(v, al2d(ans).T)))
  
      return vjp
  
file_path: autograd/autograd/scipy/linalg.py
imports: from __future__ import division
  from functools import partial
  import scipy.linalg
  import autograd.numpy
  from autograd.numpy.numpy_wrapper import wrap_namespace
  from autograd.extend import defvjp, defvjp_argnums, defjvp, defjvp_argnums
label_desc: Use image node_id 3 for calling a global function with example usage: grad_solve_triangular(ans, a, b, trans, lower) and returns: vjp, unknown