code: def find_lowest_vertex(self):
      # Find the lowest objective function value on one of
      # the vertices of the simplicial complex
      self.f_lowest = np.inf
      for x in self.HC.V.cache:
          if self.HC.V[x].f < self.f_lowest:
              if self.disp:
                  logging.info(f"self.HC.V[x].f = {self.HC.V[x].f}")
              self.f_lowest = self.HC.V[x].f
              self.x_lowest = self.HC.V[x].x_a
      for lmc in self.LMC.cache:
          if self.LMC[lmc].f_min < self.f_lowest:
              self.f_lowest = self.LMC[lmc].f_min
              self.x_lowest = self.LMC[lmc].x_l
  
      if self.f_lowest == np.inf:  # no feasible point
          self.f_lowest = None
          self.x_lowest = None
  
imports: from collections import namedtuple
  import time
  import logging
  import warnings
  import sys
  import numpy
  from scipy import spatial
  from scipy.optimize import OptimizeResult, minimize, Bounds
  from scipy.optimize._optimize import MemoizeJac
  from scipy.optimize._constraints import new_bounds_to_old
  from scipy.optimize._minimize import standardize_constraints
  from scipy._lib._util import _FunctionWrapper
  from scipy.optimize._shgo_lib._complex import Complex
label_desc: Use image node_id 7 for calling the SHGO obj's underlying member method code with example usage: obj.find_lowest_vertex() without return types